Here's a great thread over on RWI in which a member is showing side by side pics of his gen parts compared to the new V2. He lays the insert on top of the gen insert and you cannot see any difference. He said the only difference is in the right lighting at the right angle, the gen turns a sort of brownish hue. but my gosh, you cannot tell the difference at all in most lighting situations. He said, and his pics prove, that it is that freaking good. Seriously. The dial and bezel insert are fan-freeking-tastic.
http://www.replica-watch.info/vb/showthread.php/212145-Noob-Released-GMT-Master-II-v2