Resurrecting this thread to report that I purchased the latest GasOne dual fuel single burner stove, the 4000P.
So far, I like it. The biggest motive for replacing the Coleman is the lack of simmer control. I do think the GasOne IS marginally better, but it's hard to tell, since the burner does put out more BTU than the Coleman. At any rate, I still use use the diffuser, but I THINK I am getting better results. The control dial, like the Coleman's, lacks numbers, but there is wording on the dial, so you can use the letters to get a repeatable setting. The piezo works every single time, and I find that I appreciate it more than I thought I would. The GasOne's burner is designed to be more wind resistant, and I am finding that to be true, although I am not in an especially windy location, so who knows. The form factor of the stove is rectangular, so it would be easier to use a windscreen.
Works great with my Omnia.
I wish GasOne made a propane-only stove, but they don't. Also, the "User manual" doesn't address how to use the stove with propane at all. Sure, I figured it out, but it seems...odd...
I remain concerned about the line/regulator issues that others have reported. Time will tell.
So all-in-all a marginal improvement over the Coleman, for about half-again as much money. I was debating whether to keep it or not, but then this morning I decided I needed to clean it. Wow, SUPER simple. So that tipped the balance, I'm keeping it.