For extreme weather or high altitudes, experts recommend multi-fuel camping stoves, which offer more flexibility with fuel choice. Isobutane and blended propane/butane canisters are only recommended for temperatures above 40 degrees Fahrenheit. Below that, you're probably better off with a white gas or multi-fuel stove, which work best in cold conditions. Multi-fuel camping stoves are heavier and bulkier than the canister stoves discussed earlier; they also require priming, so there is additional setup time involved. Like canister stoves, liquid-fuel stoves come in two basic types -- models with the burner mounted on top of the fuel tank or those with the burner connected to a fuel bottle with a hose. Top-mounted burners aren't considered as safe, and the multi-fuel stoves that get the best reviews use a remote fuel bottle.
For high-altitude and winter camping, reviewers say the MSR XGK EX (*Est. $140) is a good choice. This camping stove burns just about any fuel you can think of, including white gas, kerosene, unleaded gasoline, jet fuel and diesel. In a test of multi-fuel camping stoves, TGO magazine recommends the MSR XGK EX, saying the stove is stable, reliable and relatively compact. It boils water quickly, and Outside magazine calls it "the most reliable stove we've used." There are some downsides -- priming takes longer than other stoves tested by TGO, and Steven Leckart at Wired finds it difficult to control the stove's heat output. The MSR XGK EX camping stove is very noisy, with one owner saying it's the "loudest stove I've ever heard...;you will shout over this thing." The MSR XGK EX weighs 17 ounces without a fuel bottle.
The Optimus Nova+ (*Est. $135) is another multi-fuel option for extreme weather, and it will burn white gas, kerosene, diesel, jet fuel and Optimus Arctic Fuel. At 15 ounces, it weighs slightly less than the MSR XGK EX, but it is still on the heavy side for backpackers. Like the MSR multi-fuel stove, the Optimus Nova+ is recommended by TGO magazine. It has a control valve on the fuel line for flame control, and Chris Townsend at TGO says it does a good job of regulating heat output. In fact, some owners say this is one of the best camping stoves for flame control. The quick-priming system also gets high marks. While Chris Townsend acknowledges that there are lighter and faster camping stoves available, he gives the Nova+ high marks for reliability and efficiency. Owners say much the same thing, although many reviewers point out that canister camping stoves are easier to set up. The original Optimus Nova (*Est. $135), which doesn't include the control valve, is also recommended by Outside magazine for high-altitude camping.
Neither the Optimus Nova+ or MSR XGK EX can burn butane, but the Brunton Vapor AF (*Est. $110) can burn isobutane-propane in addition to white gas, kerosene, diesel, auto fuel and jet fuel. The stove doesn't require separate jets to switch from canister gas to liquid fuel, but instead uses a dial knob to switch between the two. Steven Leckart at Wired.com says the Brunton Vapor AF offers "exceptional simmer control," and he finds it very easy to switch between the two fuel types. However, the Brunton Vapor AF is expensive and it's also loud, even when burning canister gas. The Brunton Vapor AF weighs 16 ounces.
The 11-ounce Coleman Fyrestorm Ti (*Est. $200) offers a similar setup, with a choice between liquid fuel (white gas) or inverted canister gas. As with any remote-cabled stove, you can use a windscreen around the burner and pot. TGO magazine recommends the Fyrestorm Ti, and reviewer Chris Townsend says it works extremely well in cold temperatures. However, he also notes that the Fyrestorm is expensive and has poor simmer control.