I'm not a big fan of polymer guns, but I've owned and used several. I've had a couple of Glocks, including Models 17, 22, 42, KelTec PF9, and Ruger LCP and P95.
The KelTec was a jam-o-matic, so it's out. It was handy sized, but even with a fluff and buff wouldn't work. I didn't have the patience to deal with KelTec customer service back then.
The Ruger P95 was my favorite of the full sized guns as far aesthetics and just overall feel. My only real complaint was that it was very slick. At the time, I didn't know about stippling, and I ended up swapping it off.
The LCP was probably the most useful to me, though it was part of a trade towards something better (Smith & Wesson 686). It was probably the nicest, as nice as a plastic gun can be.
I have had the most experience with a Glock 22, even carrying one for a few years. I don't dislike them at all, but they lack soul. They aren't aesthetically appealing or particularly historically interesting. The model 17 I had, I swapped it to a friend, but it was neat because I had a 33 round stick mag.