My first three CZ's were polymer framed guns.
The P07 DUTY (.40 S&W) has a small amount of bulge on the right side of the frame where the front metal frame insert is located. So what. It is 100% reliable, shoots like you wouldn't believe (embarrasses the S&W, Browning, XDM and Glock pistols I own - and some of the metal framed CZ's, too), feels good in my hand and was worth the expense of the RMR installation/work.
The P09 (9MM) is still the most accurate center fire semi-auto pistol I've ever shot. Too big for me to carry as long as I have the P07 but still worth the expense of the RMR treatment and it is the bedroom/range pistol now.
The P09 (.40 S&W) wasn't as accurate as the P07 or the P09 before it. Still accurate enough that when my wife shot it she completely lost interest in her XDM 3.8" 9MM she was so proud of up to that day. Forced me to buy her a CZ75 Compact so I could keep my P09 .40.
None of the plastic framed pistols have broken.
CZ 85 (Pre B) was in pretty sad condition when I bought it. There's a thread here showing all the dirt, crud, wear/tear on it prior to the rebuild. The darn thing is tough as a tank. There's another thread here showing the absolute lack of damage to the pistol after a healthy dose of Blue Dot under a 115 grain hollow point separated the whole rim of a Winchester 9MM case from the case body one day. All I had to deal with was a really dirty magazine/chamber area in the pistol and a quick field strip to dig that case body out of the chamber. Imagine what it would have looked like if it had been a glock/M&P/or other plastic framed pistol like you see on the internet when they suffer a "kaboom". Another full sized pistol, it's just bigger than I want to carry concealed.
I've got a few CZ75 Compacts of various models, bought for one reason or another (mostly - wow, that's neat looking) in the last few years. I conceal carry a couple of those sometimes, in place of the P07. There is just something about the way the P01's feel in my hand. Something I like more than the CZ75 Compacts or even the P07. But the P07 has the RMR and I feel it has always been a bit more accurate than even the P01's with the CGW barrel bushing, so it stays my EDC concealed #1 choice.
I like reliability, I like accuracy, I like a pistol that feels good in my hand. I have a safe with several brands/models/calibers of other big name makers of semi-auto pistols that don't meet those three requirements. I recently took a couple of the other 9MM pistols to the range and confirmed they won't shoot groups the CZ's shoot. Gonna try the .40's (M&P, Glock) against the P07 and P09 on an upcoming range trip.
No matter what brand is your favorite, sooner or later, you can run into a problem. Or you can perceive a non-problem to be a problem.