Another thing, 2xMSAA is faster than the lowest setting on FXAA
So if you are going to do AA as fast as possible, I'd do in this order.
1. Nothing = fastest
2. 2 x MSAA = fastest AA doable
3. FXAA, 10-39 setting on FXAA are all faster than 4 x MSAA
4. 2 x MSAA + FXAA, best looking for highest fps.
5. 4,8,16,32 x MSAA looks good but slows down quite fast.