Thermaltake looks like the better of the two, neither would be my first choice but if I did have to pick it would be the Thermaltake case. One thing to note is you should pick up one or two 120mmx120mmx25mm case fans so you have an intake fan and/or side case fan. It actually supports up to three more 120mm fans, the third spot being a top mounted exhaust if you wanted to go all out. The good news is most 120mm's are dirt cheap these days so it's not a big expense.
I was thinkin the thermaltake, but the XION looks pretty cool. Only reason I'm choosin them is money. I have 2 120MM Case fans already. Bought them with my rig, just for the sake that they could go in the case. figured a little extra cooling on a rather restricted case is better for now.
