I sold firearms for 18 years, and in that time I've seen several that cracked and blew out their commercial extractor, causing the inernals of the bolt to come out.
In those 18 years, yes, I saw "plenty" that had issues. Unfortunately, I don't have the repair invoices in front of me, I got out of the retail side of things in '05.
My father's M1A Standard, that was purchased in 2003, decided to stop going into battery while we were shooting.
He'd fire, the bolt wouldn't go into battery, and the round would not impact at point of aim. He tried one more time, after that I stopped him.
I couldn't see anything immediately wrong with the rifle so I started to field strip it.
I was holding the receiver in my left hand, my right hand had the barrel assembly. Something didn't "feel right", and when I exerted a little pressure, the barrel unscrewed from the receiver.
The rifle had less than 300 rounds through it, and was purchased new.
This happened on a Saturday. I called them first thing Monday morning. If the rifle had fired out of battery and injured my father, we would have owned Springfield.
I talked to the head of their repair dept. He agreed on how serious this was. I told them that I was going to send it in under warranty and that when I got it back, the whole rifle was going to be USGI (with the exception of the receiver of course). They were able to use the same receiver, but we got a GI barrel that they had stashed that was niw, new GI oprod, bolt, and a hand picked beautiful GI walnut stock.
The rifle was dangerous as it had left the Springfield factory, but they did make it right, their C.S. and repair dept. are some of the best in the industry.
I've also seen standard M1A's that you needed a screw driver to get the op rod out of (commercial receiver and op rods), and ones with chambers that wouldn't do well with surplus ammo, but ran fine with commercial .308 Win.
Springfield can make a fine rifle, but I would certainly look for an older one that has a majority of GI parts, especially the barrel, op rod, and bolt.
Nothing made by man is infallible. I've owned 3 Springfield semi auto M1A's (all older GI parts rifles) and one Smith Enterprises transferrable select fire M14. They're decent rifles.
I'm glad you're happy as punch with your M1A SOCOM. Next time though, instead of being a jerk on the internet, you might consider responding to someone you've never met as if they were standing in front of you.