Nano or IRC
If only one, then the Nano's would be it. They just flat-out roll faster than anything I've tried. The Bonty Jones are light, yes, but I feel like I'm dragging a trail-a-bike on hardpack. The IRC's, both Mythos and Notos, are goo too, but a bit heavier than the Nano and not quite as fast - more bite though.
The narrower options, like the Vapors, IRC slicks, and Panaracer Smokes, just don't hold enough air for my 220lbs. I'm anxious to try the Exiwolf's though also, on the opposite end of the air volume spectrum.
I have a set of Ignitors, but haven't yet mounted them. After one ride on the dos 9 with the Jones though, they are getting mounted this week.
D