For the pro hiker, avoid the Gaz stove - for a rather higher price you can get a benzene stove which is hotter, more robust, cheaper to fuel, less unstable and less susceptible to wind, cold and high altitude. I bought a Coleman Apex II, which looks like a moon landing unit and is hot as hell and a great talking point. BUT... read on to find out why I stopped being a Coleman fan.
Well, only 4 years into it's supposed 10-year lifespan, my Coleman stove decided to spring a leak in the fuel line, letting loose a gentle arc of benzene - very fortunately not spraying over the flame itself. As far as I'm concerned that doesn't consitute "fair wear and tear" - it's either a basic design flaw, poor materials, or poor workmanship. Nor can I recommend Coleman aftersale service in Cape Town, which is 100% non-existant, or in South Africa as a whole. Meantime, I no longer recommend Coleman products. Anything so expensive that (a) breaks and (b) can't be fixed at all is not a decent hiking product. If anyone from Coleman wants to convince me otherwise, I'm open to offers.
The top range of imported stoves comes from MSR, and includes the Whisperlite and XGK (what would we do without American outdoor technology? But that's another debate). They're even hotter than the Coleman range: my Coleman Apex II was once convincingly beaten by a Whisperlite in a time trial, boiling 1 litre of water at 800m altitude in a light breeze. The Gaz stove didn't even reach boiling point. But temperature control is not an option with MSR: if you want to get one to simmer, there's a complicated mantra and a chicken-slaughtering ritual you need to learn first. The only thing hotter than an MSR or Coleman stove is the debate over which of the two is better.
GETAWAY magazine once rated butane stoves as better than the Coleman / MSR ranges - but they did their tests at sea level, with no wind, and at 20 Celsius. Heck, no-one uses a stove in those conditions, and butane stoves hardly work in wind, altitude or cold. And when they say butane stoves are safer, I've seen several gas accidents on Gaz stoves when novice users don't know how to change a cylinder, so beware...