While its not the best cooler I agree with gkay. The price vs performance for the 212+ is excellent, and perhaps the best thing about it is the fans are easily replaceable. So if the cooling with the stock one isn't good enough, just add a second, or replace with a faster or quieter model. Best of all the performance IS good. More impressive when you consider its small size.
+1 @Gkay09. I just installed a Hyper212+ on a 740BE and it is very quiet, and seems to cool quite well (was around 30c before I unlocked the 4th core; unsure after that).
Otherwise, choose something with a 120mm fan; the 92mm fan on the AC Freezer whines like a monkey in the Wal-Mart candy aisle.
Check out www.frostytech.com for other HSF recommendations with reviews and audio clips.