Just set this rig up last night, very happy with it thus far.

i7 860
4GB Corsair Dominator GT 1600Mhz C7
eVGA P55 FTW
GTX 280 @ 700/1220 (will change out to 5870 next month)
TorqX SSD
Corsair TX850 psu
Vista 64



And it clocks very well, and easily. 4.2Ghz was the first OC i tried on a cheap CM Hyper TX3 air cooler and it was running 3DM Vantage and Cinebench. (took 1.35v on the chip) I won't be testing for long term stability until I get better cooling setup.

CPU-Z Validation
http://valid.canardpc.com/show_oc.php?id=728644

3DM Vantage P14305
http://service.futuremark.com/compare?3dmv=1439654

One question I do have though is what is a safe VTT? I wasn't too sure so I had used 1.4v but whats safe for 24/7?