I bought the 600W ModXtreme for my HTPC. I knew OCZ was decent. Then I read a review on johnguru.com that linked to hardwaresecrets.com and I was blown away. The OCZ 600W was absolutely lauded by the reviewer. Had no negative comments. And it was a 6 pages extensive review.
I recommend it to everyone now. Especially considering you can get a modular 700W PSU for under 100 bucks.