You're going to get too many varying opinions unless you really sit down and figure out exactly what you want.
Air or water cooling case?
Is noise a concern?
What kind of hardware do you need to cool/fit, how many GPU's, what size mobo, how many HD's?
Aesthetics- you don't want alienware plasticy, but are you ok with black steel or plastic a la HAF series, 600t, or do you want some nice aluminum panels a la FT02, 800D.
If you're just looking for the best all around air cooling case, it'd probably be the RV02-E or FT02, which also have the benefit of being pretty quiet. The HAF X/932 are also very good, though are louder and arguably slightly inferior cooling depending upon setup.
Bit Tech has a good temps comparison list here
For watercooling the best bar none would be a Case Labs ones. A M8/M10 would be fine for most needs. Very pricey though. Cheaper would be the Corsair 800D. The TJ07 would be the classic and probably most popular WC case.
The best cases for a silent build are mostly covered at SPCR, which has a nice list here.
Recommended ones are the FT02 and Antec P150
All the above range from relatively expensive to very expensive though. The best bang for buck cases are probably HAF 922, CM 690II, NZXT Phantom.
So really, you need to just come up with a better idea of exactly what your needs are.