I did several benchmarks with my system. And the higher MHz where allways better than lower frequencies but tighter timings.
So if you want some good RAM go for 1600ish@8-8-8-x. They will do much better than 1333ish.
I also read that it is common for intel systems to prefere higher frequencies over timings but not for AMD. Didn`t understand why but since i got no AMD it didn`t bother me.
Edit: This a nice Memory Performance Comparative:
And don`t think that CL7 will close this gap!Edited by Mr.Eiht - 5/2/11 at 3:48pm