I'm not a technical tester so this is just my impressions under a cold night.
VRII is good but I only pushed it to around 1/30s in a few shots. everything below was shot handheld. AF is fast and precise. the lens is solid and focus and zoom rings are very smooth. bokeh is nice IMO.
I will go back there and try to get some 1/20 and 1/10 shots. all shots below are above 1/30 and all of them are done wide open. so far so good. and yeah, no vignetting!