The Antec nine-hundred have some really decent specs. The few reviews out there all seemed to really like it since it moved a ton of air while being pretty damn quiet. I was planning on getting the NZXT Lexa, but I'm now considering this case instead.
Personally, Silverstone is too expensive for me and I don't like the way Lian-Li's look.
Lastly, the TT armor is also a nice case, but I would only consider it if I got the 25cm side fan with it...
For the PSU on the bottom, I assume the PSU will be inverted so it will draw air downwards and out... but I should confirm that with Antec themselves, otherwise then it wouldn't be as useful as it seems.