I rountinely tout the virtues of Glocks regardless of how long the poly lasts, but the one thing that bothers me is how that poly gets rubbed, polished, gouged, scratched and generally worn away, especially the exposed grip... none of it is really repairable without serious mods, stippling, etc...
I was comparing gunbroker.com examples of LEO trade-ins for the S&W 5906 and for the Glock 19 just last night.
The thing that struck me was how easily the S&W's could be stripped, bead-blasted and made to look new again with a little elbow grease and minimal expense.
The Glocks on the other hand.. they're far more involved, the finish much more difficult to replicate and the poly is nearly impossible to make look Glock-stock-new again.
Once its worn its downhill from there without obvious modifications.
Funny thing is.. the used Glocks, worn and all, still sell for more $$.