I pondered getting this through all the AF issues, and held out for a 55.... body. I don't use AI much at all, but whenever I pick it up, it focuses perfectly. I must admit that it seems to reward buying high quality lenses. I now have 5 L lenses: the holy trinity and two great zooms, and they were just meant to be used on the mIII.
My biggest problem is finding a bag to carry it all in...