My V2 arrived today. First impression: excellent for the following reasons:
The bracelet on V2 is much nicer than V1 -- more supple and bendable means it drapes nicely on the wrist.
The movement is a pleasure to wind, unlike the V1, which is finicky and a bit gritty (and then there's the working power reserve).
The crown screws in almost flat against the crown guards -- the V1 stock crown protrudes way too much and is an instant tell on the wrist IMO.
The V2 measures 9.2 mm and the V1 9.6 mm. Not a huge difference, but between the actual thickness and the way the V2 sits on the wrist, V2 feels thinner and more gen-like. (Gen is 8.52 mm according to Patek)
Onto the dial:
V2 is less iridescent than the V1 dial. Not purple to my eyes, just a little flatter in affect. They're both nice, though.
The lume on V2 is greener than on V1, which is whiter. I don't know which is more gen-like, but it'll only take a little getting used to.
The markers on V2 (six o'clock, for example) seem slightly smaller and less pronounced than on V1. Again, don't know if this is more gen-like or not, just slightly different from V1.
The two bezels look identical to me -- if there is a difference in thickness, I can't tell.
I have loved the V1 and wear it often, but I can't imagine reaching for a 5712 and not opting for the V2, which just feels like a better watch to me.