Stoves for melting snow and boiling water

I always use a WG stove. An*old* SVEA works for everything I have needed in any temperature I have ever been out in. Highly efficient with fuel, despite the priming.
It burns ~6-10grams of WG per liter on low, about 15 grams per liter on high. It does NOT burn real hot, only producing around 5000btu. So, it is nice for melting snow. The stove weighs about 19oz. And it holds about 130g of fuel. In winter it helps to have a "midi" pump for it. And, a small piece of foam to sit under it. A windscreen is important, but use caution, the stove can overheat. I prefer to have one for all camping. And I prefer an ultra reliable stove, so the SVEA Climber is the one I carry. The only thing you need to move is the valve to control it and cap to fill it. The rest is simple physics.

Alcohol does not work all that well at those temps.
Canisters also fail around that temp (unless you have an remote inverted canister stove.)
Kero stoves tend to be a bit messy and just as heavy.
Other WG stoves burn LOTS of fuel. Typically, around an 23-25g per liter, some more than that.

There are a LOT of stoves out there. Selecting a stove, like everything else, is a matter of trade offs. Reliability, efficiency (in terms of size and fuel usage), and weight in about that order.

Might wanna check out this site, Wintertrekking.com. Most members are from Canada and the northern tier states of the US where it gets cold. They seem to prefer wood, but then too, they use sleds to walk in and set up camp over flat ground.
Duane

Certainly no expert on winter stoves since I still use an old MSR Whisperlite which was handed down to me from my father-in-law, however it has worked in every Colorado winter condition that I have thrown at it (negative digits and at altitudes above 11K) and has certainly lasted me 7 years and it has been going for much longer than that before I got a hold of it– so they do last with the correct care.

My only complaint is that it is a little bulky and an awkward pack size– but perhaps this has changed a little with the new designs.

Great, reliable expedition/winter stove. Really easy to repair, made in the US. Very powerful.

I have an MSR Dragonfly that I use almost exclusively for winter camping. It's strength is its ability to simmer very low, which allows me to bake with it.

Where there is wood in winter I'd rather use my CC Sidewinder ti stove with the woodburning Inferno gassifier insert. Of course if you're stormed in you can't take it into your (well ventilated!) vestibule to cook like you can with a liquid fuel stove.

The MSR Whisperlite International is the next best stove for melting snow AND cooking. It's definitely lighter than the Dragonfly and the flame is controllable, UNLIKE the XGK stove. Controllable flame saves a lot of gas.

There are Primus stoves that are multifuel and very good as well but none can simmer as low as a Dragonfly.

For every condition you've listed I'd go with the MSR Simmerlight.

A great all around winter stove that can really pump out the heat at a light weight. I've been using mine for years with no complaints.

I’m not a wood stove user, so I won’t attempt to comment on wood.

For temperatures below about -5C, you’ve got a couple choices:
a) An inverted canister (gas) stove
b) A (petroleum based) liquid fuel stove (white gasoline or kerosene in other words).

If there’s a chance it’s going to get below about -15C, then I’d go with a white gasoline or kerosene stove.

Inverted canister stoves tend to be lighter, easier to use, and don’t require priming. The MSR Windpro is a good one (at least I have had good results with it). The Coleman Xtreme is no longer produced, but it’s the “best of breed” if you want to pick up one on eBay. The fuel is available but also generally only on eBay and is a bit pricey.

For liquid fuel stoves, any of the stoves mentioned will work. A few comments:
-The MSR XGK is the classic snow melter. Very powerful, very robust, handles wind well. Handles either white gasoline or kerosene. A tad on the spendy side. Doesn’t really simmer.
-The MSR Simmerlite is the lightest, most compact liquid fuel option out there. It doesn’t handle wind as well as an XGK and isn’t as fuel efficient. Cannot handle kerosene. Doesn’t really simmer.
-The MSR Whisperlite is the least expensive. The Internationale version of the Whisperlite can handle kerosene. Doesn’t really simmer.
-The MSR Dragonfly is a robust, powerful stove. It’s a tad sensitive and will jam if you have any lint or such in your fuel. Ask me how I know that. Unlike other MSR stoves, the Dragonfly simmers very very well indeed.
-The Svea 123 that James refers to above (The “Climber” as it is sometimes called) is my favorite liquid fueled stove. It came out in the mid 50’s and is the ONLY stove from that era still produced today. It has a bit of a learning curve, but is an excellent stove. It however can be tough to start in cold weather. Pumps are no longer produced for it, but you can get them (expensive) on eBay.

HJ
Adventures in Stoving

For all conditions you listed. Can be used as a gas stove, inverted gas stove and white gas/kerosene stove. Powerful, easy to use, easy to maintain, great simmer and not very light, but really not much difference from other liquid fuel stoves really.

Soto Muka seems good too, more pumping but so far quite reliable. Svea is really nice too, especially with the sigg cookset. Double prime if it's cold out.

For when wood is available, making a fire and cooking on it is wonderful, keeps you warm several times over. Of all the small wood burners, I like a simple hobo stove the best. Fold in a couple tabs to keep some of the wood off the bottom, plenty of air and place the pot inside right on the wood, instead of having the flames like the bottom of the pot. You'll have to keep making them though, as they do burn out over time.