Honestly, I can't tell the difference between the two. They look the same to me and feel the same when I change cables. I think if you are careful and don't swap too often, the connectors are generally fine. Of course if you put too much pressure on the plastic parts or try to force the connectors, it can crack or break over time. I have always felt I got my money out of my Shure IEMs, which is why I keep buying them (have owned the Shure SE530 and currently own the SE425, SE535 and two SE846s). I got my SE535s repaired after about 8 years of good use but I am pretty sure that was due to them being abused for many of those years (sleeping, gym, commuting and getting stuck on backpacks and train arm rests, air travel, etc.) and, in any case, I definitely got my money's worth.
I believe Shure has pretty much said the Gen 2 is really just an additional red filter (although it is a bit more difficult to remove tips from my Gen 2 vs. Gen 1 but I am sure there is a margin of error in production and they could have switched suppliers over the years). I tried to take some pictures so you can see for yourself. Can you guess which is the Gen 2?
(hint...the clear one).