Neither. Go for a Laptop with a 5850-5870m in it. I own a DV7-4060us with a Phenom II triple, 4GB ram and a 5650 1GB Radeon. Paid it 749.99 USD and most games run just fine with no AA. Cod4 and Mw2 run at max no AA, but Black Ops runs like crap. Bad Company 2 runs okay on lowest.
OP, what size are you looking to stay around? If you were considering the m11x, I assume a smaller notebook would be preferable?