i just put together an antec900 system, w/ the same mobo, q6600, and 8800gts 512mb
i wasnt pleased w/ the antec 900 case.... the hole to reroute psu wires was too small, and oddly placed... then the fans they did have in there, the wires for them were not long enough... and pretty much NOTHING in there is tooless so it took me alot longer than it would normally for me to put everything in.. and the motherboard was so close to the top, that i couldnt even properly put in a tuniq tower 120... and with the tuniq in.. the side door fan wouldnt fit!!! then the 5.25 to 3.5 bay converter was just plain confusing to me.. i couldnt seem to find out how to securely put it in.. so i ghetto rigged it some way to get it to stay in place
and for my conclusion.. i will just say, i plain hit micro and mid towers... full towers FTMFW