Can't comment on the V3, but I do have first hand experience with the V1.
1) The gen bezel does indeed have slightly different details over the rep. Shape of teeth (and precision), profile, finish, etc.
2) In order to fit the gen bezel, you need the entire bezel assembly to do it the easy way. This includes the retention ring, click, washer, etc. For good measure, I did a gen crystal and appropriate gasket as well... You can fit the gen bezel to the WM9 ring, but it will require some modification to get it to work.
I should have taken some better comparison pics while I had both, but hind sight is always 20/20; I don't have any good pics on hand now that would provide a fair representation of the two (though I do have this macro of the gen bezel)