Review: SOTO Thermostack Cooker Combo - Kill two rabbits and get several! If you have this, you don't need anything else

I'm sure there are many people who would say that the best part of going to the mountains is cooking the food on the mountain! Especially at this time of year, hot food and drinks in the cold are truly soothing and give you energy for the rest of your mountain climb

Cooking tools like burners and cookers are essential here. Cookers in particular can be used as tableware after cooking, so you want something that's easy to hold even when the food is hot, and something that doesn't cool down easily when it's cold... There are endless demands. Of course, there are products that can meet each of these needs, but when you're heading to the mountains, it's best to carry less and lighter luggage. I think there are many people who wish there was a cooker that could be used for all purposes, but still end up compromising somewhere

The SOTO cooker we're introducing this time is a cooker set that can do anything with just one set. This cooker set that meets all your needs is designed for solo cooks, but we've actually used it and evaluated it, including comparisons, to see just how versatile it is!

SOTO Thermostack Cooker Combo: Key Features

SOTO's Thermostack Cooker Combo is a versatile and lightweight cooker combo perfect for solo camping. It includes a set of 750ml, 400ml, and 350ml mugs, along with a lid. Each mug is crafted from a different metal, allowing for different uses. In addition to being able to use it on its own, the storage case doubles as an insulated case, and stacking the 400ml and 350ml mugs creates a double-walled cup that keeps food hot or cold. Its many ingenious features make it a 2019 Award Finalist in the Camping Gear category at the UK Outdoor Exhibition.

Recommended points

• This is so versatile that it's all you need
• Ensuring warmth through innovative ideas

Points of interest

• If the lid was made of metal it would be more versatile
• Tight joints

Main specifications and evaluation

The entire set weighed 306g. Below are the detailed specifications of the set contents

Container and specifications

• Mug 750 (750ml, aluminum)
• Mug 400 (400ml, titanium)
• Mug 350 (350ml, stainless steel)

From the left: Mag 750 (aluminum), Mag 400 (titanium), Mag 350 (stainless steel)

Accessories and specifications

• Magrit L (lid for Mag 750)
• Magritte (lid for both Mag 350 and 400)
• Joint (for double wall mugs)
• Cozy (thermal case)
• Lifter

Accessories: Storage and heat retention case, lid (for 750/450 & 350), joint, lifter

Detailed Review

This set consists of three mugs of different sizes and materials. Each mug is made of different materials and capacities: Mug 750 (750ml, aluminum), Mug 400 (400ml, titanium), and Mug 350 (350ml, stainless steel). By deliberately using different metals, you can take advantage of the characteristics of each metal. The inside of the Mug 750 and Mug 350 have measuring marks to indicate the capacity

The accessories include two types of Maglids (one for the 750 and one for both the 350 and 400), a joint, a cozy, and a lifter. The Maglid is the lid for the mug, and has a silicone gasket around the perimeter, which allows it to be firmly attached but not completely sealed. It has a spout and air holes, so it is useful for cooking or pouring into other containers, although it does not retain heat as well. The Maglid itself is made of resin, so it cannot be used to heat the mug

The Magritte fits securely with the gasket. It also has a spout, making it easy to use for cooking

The joint is the highlight of this cooker combo. By placing the joint between the 350 and 400 mugs, it becomes a double-walled mug with a stainless steel interior and titanium exterior. Normal double-walled mugs cannot be heated directly, but with this double-walled mug, you can remove just the inside and heat it up, making efficient use of heat and eliminating waste

If you pinch it between the mug 350 and the mug 400, it becomes a heat-retaining double wall mug.

The cozy is the set's storage case and thermal insulator. The inside is coated with aluminum film, which improves heat retention and reduces thermal conductivity when you put a mug inside, making it easier to hold

The storage case has an aluminum film vapor-deposited on the inside, so it can also be used as an insulated case

None of the mugs have handles. It's possible to hold them if you use double-walled mugs or place them in a cozy, but it's difficult to do so when removing them from the burner. You can use a lifter to hook the edge of the mug and lift it up. It's sturdier than it looks, so you can lift it without worry even when boiling water in the Mag 750

Even the Mag 700 can easily lift it

Lids in different colors and joints for double-walled cups are available as options

The lid and joint are available in three colorful options

Just changing it out can make a big difference in appearance

When you change the color, the look changes dramatically

Actual impressions after using it

Extremely versatile

Each of the three mugs is made from a different metal. Each metal was chosen based on its unique characteristics. The Mug 750 is made from aluminum, which is lightweight and has high thermal conductivity. It distributes heat evenly throughout the metal, making it ideal for boiling water and cooking. It makes sense that the largest mug, the 750ml, is made from aluminum. While it may be possible to use it for cooking rice, the included plastic lid cannot be used for heating, so you'll need to use aluminum foil or a metal lid. The lid has a draining hole, making it very easy to cook pasta and other dishes

The drain hole on the Magritte is quite useful for cooking pasta and other dishes

The Mug 400 is made of titanium. Titanium is known for its strength, durability, and low thermal conductivity. Some may wonder about its lightness, but titanium is actually heavier than aluminum. However, because it is about twice as strong as aluminum, it can be made thinner, resulting in less weight. Its extremely low thermal conductivity means the rim doesn't get hot even when filled with hot liquids, making it an excellent single-wall cup. Its low thermal conductivity means heat doesn't transfer throughout the cup when placed over a fire, making it unsuitable for cooking. However, its high specific heat capacity and thin construction make it quick and easy to boil water

The Mug 350 is made of stainless steel. It's rust-resistant, durable, heavy, and has low thermal conductivity. It's extremely durable, so you can use it without any worries, making it the ideal metal for outdoor activities. However, it's heavy, so its use is limited. Its low thermal conductivity and specific heat make it slow to heat up, making it unsuitable for cooking or boiling water, but once heated, it retains its heat for a long time. If your drink starts to get cold, you can remove the Mug 350 and heat it over the side flame

The Mag 350 is made of stainless steel, and the Mag 400 is made of titanium. The Mag Ridge is for both

Considering the properties of these metals, this cooker combo is very well thought out and well-balanced. The Mag 700 boasts the largest capacity, and is made of lightweight, heat-conducting aluminum, making it easy to carry and ideal for cooking. Despite aluminum's tendency to heat up and cool quickly, the cozy storage bag allows you to hold the mug even after removing it from the heat and retains its heat. The Mag 400 is made of titanium, making it lightweight and durable, and easy to use as a mug even after heating it. This is the mug you'll likely use most frequently on its own. The stainless steel Mug 350 is likely to be used less on its own than the others, but its high durability and easy maintenance make it highly user-friendly

This combination of titanium and stainless steel is perfect for a double-walled mug. The stainless steel inner wall, which retains heat once heated, and the titanium outer wall, which resists heat transfer, make this a perfect double-walled mug design, preventing heat loss due to the outside temperature even in cold environments and keeping the inside cool. The joints are a little tight, so care must be taken when removing them

By inserting the joint, it can be used as a double-walled mug with a titanium outer wall and a stainless steel inner wall

Despite being such a versatile and versatile combo, it weighs just 306g including all accessories. Considering all this functionality, this weight is quite light. If you want to make it even lighter for solo use, or if you don't need the double-walled cup in the summer, the total weight is just 220g, and if you don't need the lid, it's under 200g. Storage is also excellent, with everything fitting inside the Mag 750. The double-walled cup can accommodate a lifter and a small burner

When stored, the Mag 350 can accommodate a lifter and a small burner

If you put the double-walled cup upside down, the lid acts as a buffer and prevents the unpleasant sound of metal hitting metal. Incidentally, small gas canisters fit snugly into the storage bag

The Cozy and Magritte are just big enough to hold a small gas canister

Heat retention verification: No difference to a regular double-walled mug!

To see how much the heat retention differs, we filled each of the Mag 750, Mag 400, and Mag 350 with half the capacity of boiling water, closed the lids, and measured the temperature change after 30 and 60 minutes. The test was conducted indoors, with the indoor temperature at 17.5°C

Next, we attached a Cozy, which doubles as a storage case and thermal cover, to the Mag 750, and used the Mag 350+400 as a double-walled cup to measure temperature changes. To determine whether the Mag 350+400 truly functions as a double-walled mug, the Snow Peak Titanium Double Mug 300 and the Coleman Double Stainless Mug 300 and performed the same measurements.

When left as is, the temperature dropped to about half in 60 minutes at an outside temperature of 17°C. I expected that the titanium Mug 400, which has low thermal conductivity, would have better heat retention, but in fact it was almost the same as the aluminum Mug 350

However, with the Cozy attached or the double-walled mug, the temperature after 60 minutes was about 10°C higher, suggesting a more effective heat retention. Compared to the Snow Peak and Coleman double-walled mugs, the temperature after 60 minutes was roughly the same, demonstrating that the double-walled mug functions well. The Mug 750+ Cozy's heat retention is also sufficient, with 90°C water remaining at 50°C after 60 minutes

Convenient usage that makes full use of containers and accessories

As an example of convenient use, which is introduced on the official website, I tried out a method of making coffee that makes good use of the double-walled mug. It does feel inconvenient without a handle, but once you get the hang of it, it makes you realize that you don't really need a handle! First, boil water in the Mug 400. While that's happening, prepare the dripper in the Mug 350

Since it has no handle, you need to make sure to balance it before turning on the heat to boil water

Once the water boils, use the lifter to pour the water into the Mug 350. Everyone has their own preferences when it comes to brewing coffee, so feel free to do it your way

Use the lifter to pour hot water into the Mug 400

Once you've finished brewing your coffee, simply attach the Mug 350 to your 400ml mug to quickly transform it into a double-walled mug. Even if there's still boiled water in it, simply attaching it will slightly improve the mug's heat retention

Once brewing is complete, stack it on top of the Mug 400 container to improve heat retention and make it possible to hold it in your hand without the lifter

With a bit of ingenuity, you can use both mugs for a variety of purposes beyond just coffee. That's one of the fun things about them. When the mug gets cold, you can just take out the Mug 350 and heat it up. I also tried cooking with the Mug 750. When I say cooking, I mean just making ramen... but if you put the freshly made cup in the cozy, you can hold it in your hand. It keeps the temperature better, so there's nothing to complain about. The handle is fragile and adds a little weight, so maybe it's actually not necessary

Putting it in a cozy will improve its heat retention and make it easier to hold in your hand without the need for a handle

summary

The Thermostack Cooker Combo is not just a set of cookware in convenient sizes for storage. It takes advantage of the properties of metal to offer the widest range of uses with the smallest set. It didn't win awards at outdoor exhibitions for nothing! When you analyze it like this, you can see how much thought went into creating a cookware set by SOTO, which is difficult for any manufacturer to distinguish

This single set is all you need for solo mountaineering, and a full set for more relaxed hiking, allowing you to fully enjoy hot food and drinks. For ultralight hikers who are concerned about weight, depending on the combination, this cooker will be lightweight yet fully equipped. It's also a cooker that can easily accommodate two people if used properly. The double-walled mug, which is the highlight of this cooker, offers comparable heat retention to other companies' sturdy double-walled mugs, demonstrating its excellent performance

If you're looking for a cooker but don't know the differences and don't know which one to buy, this one will last you a long time, so you won't regret it and you'll be able to use it for a long time to come. On the other hand, I would also recommend this to people who have tried and used many different cookers in the past! Hats off to the manufacturer's efforts and ingenuity, and your love for cookers will only grow stronger

   

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