So say I were to upgrade would you guys recommend the Z68 Extreme4 or the P67 Extreme6. - I have no real use for the extras provided by the Z68 chipset.

Does the "V16 + 2 Power Phase Design" really make that big a difference when overclocking as compared to the V8 design on the Extreme4?

They are the same price for me at Newegg and I have Shoprunner thing so shipping price is not an issue.