Well I have the Zalman GS1000 SE and I really like it. It has quite a bit of room, although not as much as the 800D. There are also the GS1000 and the GS1000 Plus (which looks like it would improve on air cooling)
You can have hot swap with the GS1000 and GS1000 Plus and with an extra board you can do it in the SE version
NCIX.com - Buy Zalman GS1000 Plus Black Aluminum Full ATX Tower Case 4X5.25 6X3.5INT No PSU Front USB E-SATA Audio - GS1000+ B In Canada.
I will say that if I could get it right now I would get the Plus version as my temps are fine but my drives are a little bit warmer than before. I did add a fan to the bottom and to the top, that I'm sure makes a good difference.
Oh and it is about $70 cheaper than the 800D.