I use MYOG Super Cat and Penny stoves--paired with a wide-bottomed aluminum pot, both will bring 2 cups to near boil in 5 to 6 minutes.
For a narrow pot, I use the "Half-Penny" alky stove, or Snow Peak GS100 (manual ignition, ~$40) canister stove. With the canister stove throttled back for max. fuel efficiency, there's no real difference in boil time between the two--if anything, the alky stove is a bit faster.
Testing indoors with water around 70 F, I can bring 2 cups water to near boil with either 0.5 oz by volume (12 grams) of alky (Ace hardware shellac thiner/stove fuel) or 5 grams of canister fuel.
In my experience, the Super Cat does fine *if* paired with the right pot and is almost fool-proof to make. The penny stoves require a bit more care to build, but are pretty efficient, and fast for alky stoves. I suppose I could run my SP canister stove at max. and boil 2 cups more rapidly, but I'd pay for it in fuel efficiency. For a 7 day trip, that would mean carrying 2 canisters instead of one, and that's real weight.
For me, the Snow Peak is a bit more convenient than the alky stoves, and is a jewel of engineering--I love using it. But the alky stoves were virtually free, and I like using something I made myself to prepare a meal deep in the backcountry. I love the simplicity and silence of alcohol stoves.
Backpacking teaches me patience--if a minute or two faster is that important, why am I walking?