V600 case is really restrictive on HSF...Tuniq won't fit. Most non-stock HSF won't fit according to what I've read. I actually ordered the A05B case from NewEgg earlier yesterday afternoon after a good month's worth of case choosing, comparing, and debating.
My new build will have a Q6600 and a Tuniq and they both work in the A05 because there's nothing blocking the Tuniq. That's the one thing I didn't like about the V600...the PSU mount is in a really odd place, right in front of the mobo. If only they'd move the mount to the front with an extender cord like on the A05, I think the V600 would be a perfect case.
As for noise on the Tuniq, it's one of the quieter HSF out there from what I've seen; there's plenty of Tuniq reviews, links, and info here on AT.

Originally I was going to get the Arctic Cooling Freezer 7 Pro for the Q6600 because I don't plan on much overclocking (just the free 25% increase by bumping the FSB up to 1333 on the Gigabyte P35-DS3R mobo I plan on buying)...but the thing that irritates me about the Freezer 7 Pro is it uses those stupid plastic clips that the stock LGA775 HSF use and I don't trust it; I'd rather have a screw down design like on the Tuniq.