Quote Originally Posted by HHollow View Post
I am a polymer engineer and I love plastics of all kinds. I agree that a polymer lower would hold up (longer) if designed from the ground up. However, I would not use polymers on anything I would need to still be functional after 20 years. Polymer simply does not age well. Oxidizes, stress cracks, embrittles, light induced decomposition, plasticizer migration, etc. Many folks who make thinks out of commercial polymer formulations have no idea what research is really necessary to show long term durability.
I certainly know of polymer items that literally fell apart in 20 years or less, but also know plenty of polymer items far over 20 years old that are going strong. Glock pistols and mags for instance.

Andy