I have been running a BFG setup with 680i and 8800GTX in the HD160 for 5 months and heat is not a problem.
It does just fit. The end of the card is very close to the Hard drive rack, but if you either do a minor mod (as i have done to just move the rack a few mm forward, or leave the end HD slot free it fits fine.
Contact me if you want any details of the mod. I may well be parting with mine soon as I run it as a workstation and need more HD space, other than that the case is a top product.