I have almost the same setup as you, and to be honest I don't know why you need 16gb of RAM. I use 6gb of OCZ RAM with a low latency time and it is way more than enough.
I will also be running Virtual machines. So the extra memory is so i can have four or five PC running at the same time all on the one box.
i ended up getting the 1600mHz memory and changed the board to the P7P55D-e PRO.