I would try to demo a DLP projector on a darkened HT environment, rather than an office environment. If your one of the unlucky people that suffer from rainbows, it will bug you. Also, if rainbows don't bother you, make sure they don't bother any significant others
Personally, I have always taken the LCD route, not becuase of rainbows, but that usually you can get into higher resolutions for a much lower price than DLP. Also, SDE (screen door effect) is not just an LCD characteristic as some believe, DLP's also have SDE. LCD technology has improved so much over the last few years that SDE is not an issue.
good luck
m60's vp150 ep350 4-Qs8's
denon 2805
Sanyo Z2 WXGA projector
toshiba dvd
samsung hd receiver