If you don't mind the price, the size of the butt-ugly look, the Noctua NH-D14 is definitely a good contender. It will cool very close to the best, but the varying speed fan will make it whisper-quiet when you don't need that much cooling. Another good contender is the Tuniq Tower 120 Extreme, still one of the best cooler out there, cheaper than the Noctua, a bit louder at low speed, but quieter than most at full speed.
I have the NH-D14 with the 2500k. I love it. It's big, but who cares if you have the space? One thing I love about it is how flexible it is iwth the setup. You can run both fans, or just one, or just the heatsink if you're confident in your case cooling. I'm using an FT02 so I'm thinking after I get my desired clock speed/temp, i'm going to slowly turn down the fans and remove them to see how quiet I can get the box.