I have the Iwill KK266 and run my Tbird at 1500MHZ. I use a Globalwin FOP38 with the hideously loud 7000RPM Delta fan. My cpu temps never go over 43DegC, but the noise after three months is getting annoying.
The SK6 wasn't available when I built this machine, I wish it had been. The Sk-6 can achieve almost the same level of cooling with a less obtrusive fan.
You wanna talk loud? I carpeted the inside of my case, the case exhales though a chimney, while the rear area is packed with old comforters to quelch the sound. With all of that, I can still hear the darn thing in the next room, if all else is quiet. I didn't think it would bother me at all, but it does. So you may want to opt for another fan.
So, my 2c says go for the Sk-6 with any other fan than the Delta.
OCnMan