I've been considering going Sandy Bridge for a while now and I'd like to achieve safe stable 24/7 clocks in the upper 4's to 5 Ghz if possible. Could I do that on a 2600K? Yea, probably. But to me a "safe stable 24/7 clock" is one that passes significant time on prime 95 (10+ hours) and never exceeds 70-72 on the cores. I have a much better chance of achieving that with a 2700K than 2600K.