QS,
Sorry about the delay. I think this post belongs more in the 1911 column, but here it goes, regardless...
I bought a Colt Government Model (Mark IV, Series 80) NIB from a dealer way back in 1991. Paid a whopping $480 for it, with fixed sights, and a great Colt Royal Blue finish.
Went to the range - immediately had problems with the gun. Failure to feed, double-feed, you name it. ALL magazine related. While I'm not sure as to when Colt started doing it, they went to a conversion kit from a company called Shooting Star - instead of designing an 8-round magazine on their own. For some reason (I guessed weak springs at the time), the mags never worked properly.
I trashed both of the factory Colt mags on the scene, used a couple of older GI mags that I had inherited for the rest of the day, then ordered a few Wilson #47D's (I think - I no longer shoot M1911's). I was very pleased after that with both the weapon, and the fact that it was 100% reliable.