Any heatsink performs better if you don't care about noise. Tuniq tower was on that power system with a q9650 running at 4 GHz that made the home page last week. not bad at all, but not quiet. The TRUE will do better at low fan speeds, but any of the big ones will do pretty darn well to a point.
I use the Tuniq, it was cheap, i put a quieter fan in so it's hardly audible if i want it to be. 3 GHz q6600 does not phase it. 3.2 GHz 8x400 requires more fan speed. 3.6 max fan speed (may as well use fan it comes with).
I would avoid anything you cannot replace the fan on, (zalman). Not having the ability to replace moving parts is a bad design.