I love my simmerlite. It is lighter than a whisperlight, the fuel line has a smaller volume so it is more responsive to changes in the valve. It doesn't simmer ultra well unless there isn't much pressure in the fuel bottle, but you can achieve a very good level of flame control if there isn't much pressure in the bottle. I cooked on mine exclusively for 2 months on a climbing/road trip and had no problems. It primes on the burner which is different from a whisperlite but uses less fuel and is effective at priming the stove. The one draw back to this stove is that it only works on White gas so it isn't a good stove for international travel, but other than that, it is perfect.

Extremely light, very small, very accurate and responsive simmer control. This is an excellent product and I recommend it with no hesitation. $110.00 @ MEC