Why I don't like plastic guns? Well lets start Glock like handling a 2X4. Blocky and cheap feel. But for all polymer guns short life. I have my Dads S&W he carried in WWII it still shoots like a dream and someday I will pass it on to my son.My other guns 686s, 1911, AK47, Ruger MKIII and my Marlin 22 carbine same will be pass on to future gun lovers. Can anybody say that about the plastic guns? No because plastics breakdown under UV light and oxygen/ozone. I asked my son, who has a degree in organic chemistry, ad he said the same thing. Also the constant flexing from the shooting will eventually fracture the plastic especially after the plastic becomes brittle from the oxidation.
As for those that think just because the Military uses it its got to be good, Sorry. Remember the DOD buys cheap. The DOD buys low bid and it is a break and replace not fix.If it breaks or wears out give out another contract to replace it and defense contractors love it.