Best simmering stove, PERIOD
I use my Dragonfly stove these days exclusiely for winter camping. It is HOT when I need to melt snow for water and it simmers very low when I want to bake with my Backpacker's Pantry Oven.
I've owned my Dragonfly since 1994 and it has never given me a problem. I did replace the original MSR pump only because I heard the newer version was more durable than my original pump. So far both still work fine.
My only quibble is that MSR did not serrate the top of the wire pot supports for better "gription"
so I filed many small Vs in the pot support topsides and all is well.