In your OP you asked for a review. I have a Gen4 Model 19 and have run 200 rounds through it. It's incredibly accurate right out of the box and holds a nice tight pattern. It's also a genuine pleasure to shoot. Very little kick or rise off the target. It's easy to bring it right back in for another shot.
However -- In those first 200 rounds I had 3 FTE (failure to eject). I had to rack the slide to make it right. Then it would go right back to work.
I emailed Glock about it and they had me take it back to the store (where it is now) to have a new ejector put in. So get yours out there and put some ammo through it. If it acts up at all, call or email or call Glock to have them make it right for you.