Cool beans, you should even be able to do small overclocks with that cooler. Here is a review i found of it with a 2500k at 4.5ghz with load temps of 66c.
http://aphnetworks.com/reviews/silenx_effizio_efz_80ha3
If you get bored down the line i would shoot for a 4.2ghz 4 core overclock for your 6600k, this cooler should be able to handle that if you keep the volts under 1.2.