MoBo / CPU - The Asrock boards only come with a 1 year warranty, the upped it to 2 years on the B3 P67 ones after the recall.....I'd want a industry standard 3 year warranty. This Asus P9P67 Pro combo gets ya three years at the same price.
Antec DF-85 ($170) w/ CP-850 ($120) or HAF-X ($180) w/ Corsair AX750 ($170) ..... if ya like the Seasonic's you'd want the X series Seasonic X-850 . Both cases are great for performance systems tho, having built with both, I have to give the edge to the DF (not to mention the $60 price difference). All three PSU's are 1st tier, get 10.0 performance ratings from jonnyguru and will handle twin video cards.