I totally respect the P67's, Intel Nazi approach to crippling the x8/x8 is all out of greed to sell X68's is waht it is also.
I think you decided on the ASUS which, trust me, once you fire it up you'll be Yeah Haw - Holly Smokes! Yeah Buddy - Who's your Daddy to 99.99% of the folks out there!
Meanwhile the ASUS Maximus IV with it's P67 + nVidia is BSOD'ing...
Just be very thankful you didn't get the UD3R -> http://www.tomshardware.com/forum/276715-30-x58a-ud3r-raid-bsod-disk-boot-failure
It was meant to be -- enjoy!