As a bit of a preface, i've owned dozens of GEN's and maybe 2 dozen REP's, AP's, Rolex's, Omega's, Cartier's on both ends. TC's on the REP side. Truth is, REP's just aren't as solid overall as GEN's at least until they turn into some serious franken watches at which point they're at 1/2 the price of the GEN and starting to use actual GEN pieces.
That being said, i've been out of the REP game for over a year now and I haven't had a V7 Noob Sub yet, but might take the dive (hehe). The last one I got - the V5, neither looked nor wore anything like my gen Sub-C, I got rid of it ASAP.
I think the little details in the gen's add up significantly. There are a few watches that do look very real though and wear much like the real thing, the AP Diver for one, and many of the PAM's since their cases don't have many parts or detailing to them. It's the complicated things like the link bracelets, or the jewelry-like detailing or Rolex's that make GEN's seem different from their REP counterparts (although like previously mentioned - this doesn't seem to be the case for the AP line).