i live at 8500 feet and have backpacked (not hunting, though) to over 14,000 feet... my favorite stove is the SVEA 123 (now optimus?)... it's a classic design, about a century old if i'm not mistaken, simple to operate (a bit finicky until you get the hang of it) and doesn't need any pumps or attachments, etc. and will run on unleaded gas and coleman fuel... some folks hate 'em cuz they're not all modern and "techy", but what you'll hear over and over again is "i've had mine for 50 years and it still works good as new" or "had mine in storage filled with gas for 20 years and it started right up!"...
if you like your stove a little more high-tech and if the ability to control the flame from simmer to full-on roar is important, i like my brunto nova (also optimus now, i think?) quite a bit... it'll burn most everything (except alcohol - alcohol isn't sufficiently volatile to produce a good flame in a gas stove.) it's a great stove, but i like to keep things as simple as possible and all that control comes with a price: more parts, more stuff to lose, break, etc... but i still wouldn't part with mine... great stove...