I've owned a Gen 3, G19 for about 12 yrs now and absolutely love it. Probably the sweetest shooting gun I own. My question is what are the differences (other than grip) between a Gen 3 and 5? I'm thinking about trading in the Gen 3 for the Gen 5 but not sure what the net gain (if any) there will be. I appreciate your comments!
Gen 3, 4, and 5 G19s owner here. Gen 5 keeps some of the good gen 4 features (like factory texture, back straps, larger & reversible mag release) and added ambi slide stop, (slightly) improved the trigger, ditched the finger grooves, flared the magwell, 3 factory sight options, and added a barrel that's capable of a little improved accuracy over previous gens. There's more changes, but those are the main points worth noting IMO.
The new finish, everybody likes to whine about, is incredibly irrelevant to me after the first couple days. I wear on every firearm's finish I've ever owned.. Probably because I actually shoot my guns.. However, it is a little slicker, so it can be a little more difficult to grip for some people, but it is supposed to help with running longer without lubrication. The next thing people have been whining about is the return of the half-moon cutout at the bottom of the front strap. Mine does not bother me at all, and FWIW I have large hands. Nor do I know anybody that owns, and shoots, a G19.5 that has real issues with it. The frame bevel matching the slide is another thing - that looks like has been cleared up by Glock anyways - again, incredibly irrelevant.
All that said, and like I've said in the past - I wouldn't feel "compelled" to trade up to the gen 5. If you can, and want to, go for it! - it's REALLY hard to go wrong with a Glock!