I'm another Infinity owner (about the same height/weight/shoe size). I've also ridden Arbor and GNU.
I kind of agree with what Noreaster said. I've ridden ice on the Infinity, and as long as your edge is sharp, and you're not trying to speed-carve icy double blacks, the Infinity can handle it well.
For me at least, the Infinity is really damp like people say, and it's on the heavier side.
I do like GNU's C2BTX boards though (I hate hate hate their rocker boards). I imagine that the serrated edge would be really good if you ride in icy conditions all the time. Their boards are definitely lighter. I don't like how their tips are unprotected though (no metal edge on the tips! they get scuffed really badly).
Never Summer - heavier, damp, durable, great for high speed cruising
GNU - lighter, maybe holds edge on ice better
I have never tried the Lotus, so I can't say how it compares.
One board I've always wanted to try is the Smokin Vixen. It has GNU's magnetraction (supposedly a bit less aggressive?). But it's an all-mountain true twin, and it looks like you're looking at Directional boards.
I actually like Arbor boards a lot, but it's more of a light, nimble, playful board. It still rides groomers very well, but the board I rode (Cadence) is very different from the Push.