The DK1 is just awful in comparison to the DK2, though. Positional tracking and reduced latency of the DK2 improve the nausea situation a whole lot. I haven't had a chance to try the CV1 yet, but it's supposed to be an equally big jump.
I haven't tried any other VR devices yet (skipped the DK2), but I look forward to demoing the CV1 at some point. Since Linux support has been killed, it will probably be a while, whenever I get around to building the separate free-standing Windows machine I've been intending to get for the last year or so (with dual-boot, I find I boot up Windows once a year, or twice if MS is lucky that year; I just have too much stuff running on my primary workstation to let it go powered off for very long).