Very good stove
I use the Simmerlite as a cold weather alternative to my Coleman Extreme canister stove. The Simmerlite performs as advertised. The folks who are having trouble simmering probably have the unit over-pressurized. I start with only 8-10 strokes of the pump. I prime the bowl by opening the valve one turn for 3 sec and closing quickly. I light it, let it flare and then die out. I immediately crack (just barely) the valve and re-light. I get a nice gentle blue flame. I then pump a few strokes as needed, but certainly not the 20-25 strokes suggested in the instruction manual (unless I am in a huge hurry to boil water and not interested in turn-down). This technique works for me every time.