I'd go with Gigabyte. Asus have a horrible track history on RMA, and AsRock aint far behind. Gigabyte, love story for me so far! But i have yet to own and use a Gigabyte motherboard daily, which annoys me, cos i want one, they just wont make one that fits me.
Also, is Dominator ram really needed? Are you going to be overclocking the balls of the ram? Might aswell just get som Crucial or G.Skill at half the price.