Just picked up the 55 yesterday to beat the price increase. My first non-LM G mount lens. I'm sure this has already been said (didn't read the whole thread), but...
IQ: In a word, wow. Even wide open. Just lovely.
Bokeh: Again, wow. Insert the usual terms . . .creamy, etc. Really sublime.
AF: Wow again. But this time, wow, it sucks. Slow. Noisy. Hunts. Pulses - even when I'm not trying to focus (like when chimping).
Hummm...got some thinking to do as to whether this one remains in the stable. Might need to brush up on my MF skills.