We have had a chance to use the MSR Whisperlite International multi-fuel backpacking stove several times in a wide range of condtions with great results. Here are our findings:
We purchased the stove for two main reasons. The first being the fuel bottle, which is sold separately, is removable from the stove and seals very well for storage and travel in a backpack. We also found the stamped stainless steel legs of the stove fold down very small for packing with a light travel weight of 14.9 oz. We also really like that the stove came with a stuff- sack that the burner, priming pump, and related parts all fit into very nicely.
We have only used the stove with white gas and originally had some problems achieving a good hot flame. We thought the older fuel we were using may have been the problem and switched to a fresh can of MSR Superfuel which delivered very impressive results. We got a fast pre-heat of the stove and a great clean blue flame when the valve was opened after the pre-heat with the MSR fuel.
With pre-heating the stove, it is critical to set the stove on top of the included reflective circle and wrap the reflective sheet around the stove. This will help reflect all heat back at the stove to help the fuel tube heat-up quickly. It is very important to get the atomizing tube as hot as possible when pre-heating, as it is critical for a good cooking flame when the valve is opened.
We have found that the stove will heat water to a boil in a very respectable time-frame. MSR reports that with white gas, it will boil one liter of water in 3.5 minutes. We used the stove in rain, wind and subzero temperatures with blowing snow with 25 mph winds, yet had no issues pre-heating the stove or bringing water to a quick boil. The stove generates a massive amount of heat and as said before, it is critical to use all included reflective panels to direct the heat to the intended surfaces. The reflective panels also do an outstanding job protecting the stove from heat loss in high winds.
The stove is very easy to unpack and assemble while wearing thin gloves on your hands. We tested the stove in Eagle Harbor, MI with temperatures of only 7 degrees Fahrenheit and steady winds. We had the stove packed in our backpack in its stuff sack and the fuel bottle removed and sealed while stored in a separate external pocket. Once the 6.25 mile hike, with 900 feet in elevation gain was completed to the top of Mount Baldy, we arrived to find winds blowing 35 mph plus and temperatures dropping at the peak. We were able to quickly remove the stove from the backpack and assemble it with gloved hands. The stove quickly pre-heated even in the declining weather conditions and was able to go into cooking mode smoothly with a solid clean flame. The water we brought started freezing in the water bottle but the power of the stove was able to quickly bring it to a boil, nicely tucked in the reflective panels. The result was a nice hot cup of soup to warm the soul before we bailed out on the mission as the boots we had on our feet did not pass the test this day.
We were originally concerned with the field assembly of the stove and operation as it seemed a little bit more involved than a one piece stove. With some reading, as well as watching a few YouTube videos, and of course, practicing at home, we quickly became pros. The other feature we found we really like is that the stove is very field serviceable should you have any issues when out on adventures. We had all the confidence in the world when using it on top of the mountain in poor weather conditions. The Whisperlite stove has earned its spot as our main stove for light-weight missions where reliable equipment is definitely needed.