I have the 900 and it kicks ass. It lowered my northbridge temp 20C, no lie. Thats mainly because I have an accelero x2 that used to heat it up to 50c, but now it never breaks 30c. All of the fans are very quiet on low and medium, and the 200mm on top is just a beast and is very nice to have if you can "aim" your cpu cooler. I give it a 2 thumbs up and I got mine for $117 shipped from www.provantage.com Hope this helps!
Question for the 900 owners...what the hell is up with the PSU bay? Maybe its just that HP PSU I have in their temporarily, but mine would not fit. Only Antecs or something fit?