Eight years after my Standard Products M1 Carbine went kablooie, I finally picked up another GI-spec rifle.
Back in 2002, I was firing my Standard Products M1 out in the cold when I had a failure to fire. Bang-bang-nothing: dead trigger. I tapped the magazine and racked the charging handle only to have the bolt fall into three pieces. I consider myself lucky I didn't have a catastrophic failure and blow my face off, but I knew I needed a new bolt (at least). I sent it to Fulton Armory, who had previous done a good job rebarreling my M1 Garand, only to have them tell me the chamber was buggered up. They wanted another $300 for a new barrel, based off of damage that I couldn't see. I ended up selling the carbine sans bolt (with full disclosure) for $140.
Two years ago, I bought a Universal M1 Carbine, hoping it would be at least a good shooter. During disassembly I discovered just how different they are from GI-spec, most notably because I couldn't reassemble the trigger assembly to save my life. I never fired it, I just had a smith put it back together for me and returned it to the dealer. Fortunately I got a full refund for my trouble.
Yesterday, I rectified that error with a National Postal Meter M1 in good condition; bright shiny bore, bluing near 99%. It is a Blue Sky reimport, with an Inland barrel, but I intend to shoot it, not make money. I'm keeping my fingers crossed that it will run well, and with a newer-style round bolt I don't expect it to fall into pieces on me.