I've seen some image samples from FD lenses on the A7r. If you want info on the metabones adapter, I would guess the reviews from the NEX line of cameras would serve you well. The information on the phase detect pixels is a little sparse, but I gather that they are mostly used for tracking subjects (they can tell the difference between something moving away and toward). I do not know that the A7 has faster AF when using them (though it may). I expect that the phase detect will work for any lens the normal AF works on, as they're on the same sensor.