The artic freezer pro is quieter (apparently) which is good as I sometimes play games in my room when my girlfriend is asleep and I sometimes get kicked out (like last night) when my current stock fan goes nuts (one core is constantly at 69 degrees under load). On the other hand the hyper 212 is apparently a bit better at cooling, it is a toss up.
I also hope they fit into my case, I can't believe how long they are.
I am thinking of getting the cooler, sticking with the Q6600 until a good sale comes along on a more modern CPU and getting a new GPU now. There is alot of talk of the GTX 560ti being an excellent card and with the money of a GTX 260 going towards it it may be a good idea.