I got my Ultra-D moded so it can take Dual Cores, and i also got a new fan because i sorta ripped my out...
It's quiter then my video card fan lol...
I donno, ASUS A8N-SLI Premium, and Ultra-D are about the same, I found asus 100$ more from where i got it. It really depends:
DFI: COOLNESS, COLOURY, CHEAP, SIMPLE.
ASUS: SLICK, DULL, EXPENCIVE, QUITE, COMPLICATED.
THat's totaly my opinion thoe...