I had the Western Digital Black Drive, 1TB WD1001FALS SATA / 32MB Cache with a Hitachi Deskstar 1TB May 2007 SATA 3.0 7200RPM together in my Corsair Carbide R100.
I took the drives out because they got really hot and I was afraid they were going to melt the plastic hard drive rails. :-(
I'm not intimately familiar with that case (although I have I think the same one behind me, but I haven't given it a through look-see yet), but generally-speaking, if you have two 7200RPM HDDs, you DO NOT want to stack them DIRECTLY on top of each other in a chassis, WITHOUT active cooling. That's just asking for problems. Generally-speaking, again, 5400RPM HDDs run cool enough, that this isn't a problem.
Most cases with stacked 3.5" HDD bays, do have a provision for a fan mount, either an 80mm or a 120mm, even if the chassis doesn't ship with one pre-installed. Only the poorly-designed cases will lack a chassis fan mount near their drive cages, or they will utilize an alternative means of mounting 3.5" HDDs. (For example, one of my cases has a mounting frame tray, that then screws flat against the back of the mobo tray area. There's one 2.5", and a couple of 3.5" trays.)