OLDSTER, with respect to polymer pistols, I can only speak to Glock and Sig pistols. I have a number of Glocks and 2 Sigs (P365 and P320, which were prizes). I prefer the grip angle and trigger on the Sigs, and the method of take-down.
On the flip side, I have mostly Gen 5 pistols, with 1 Gen 4 (G30). I am in a position where I can shoot them well. I think that the best motivation with the Glocks is the Glock Sport Shooting Foundation events. Depending on the area, you can find outdoor matches and Indoor League matches. With the GSSF events, you have the opportunity to win money, credits towards membership renewal or entry fees, and either performance/random/drawing pistols. This is something other manufacturers have yet to catch on to.
The bottom line is, get whichever you prefer and suits your needs. Just a quick note, if you buy a Glock for the GSSF matches, they need to remain pretty much stock. Also, if you are leaning towards a Glock, join GSSF first so you can benefit from the Blue Label discount coupon, where you can purchase a $600 MSRP pistol for $425!