I shot the Polymer 80 "Glock 19" last night. My dad and I put about 150 rounds through it, mostly Herter's 115 grain ball (made by Sellier & Bellot), along with around 25 rounds of my handloads. They were 115 grain Berry's plated bullets on top of 4.5 grains of Universal Clays in mixed brass.
The gun had one malfunction, a failure to fully go into battery with one of the handloads. Previously, I had some issues with this batch in my CZ P-09. AFAIC it was an ammo issue, not a gun issue.
Accuracy was OK, nothing to crow about. Most of the rounds went into a palm-sized group at 7 yards. The limiting factor for me was the trigger. Even with my fluff and buff job it is still pretty bad -- heavy and creepy. I'll see what it feels like after 500 rounds but if there isn't a marked improvement I'll look into getting something like an Apex trigger.
The other mod I have tentatively planned is a set of Heinie Straight Eight night sights.
After I finished shooting I field stripped it and saw no signs of unusual wear.
So far I'm very pleased with the gun.