I feel the same way - I really dislike Ebay and feel I can trust buyers here. I'm completely unfamiliar with those Epson projectors, can I use them for home theater eaily? From initial searches it appears that they are primarily computer projectors.
It's not an X1-specific issue. I see rainbows on all DLP projectors that I've seen, and the X1 isn't particularly bad. In other words, it's me, not the X1. The only way to tell if you'll be affected is to see it in person. Shoot, for $650 I'd buy the projector just to try it, and if you're bothered by rainbows sell it again. Plenty of people out there aren't rainbow-afflicted.