Carbines are great. Fun to shoot and easier to score hits with than a sidearm. Never had problems with GI extractors, but all the ones I’ve fired weren’t reliable with aftermarket 30 round magazines. Korean made magazines seemed good to go.
You’ll hear people say the round is a pipsqueak, hardly more dangerous than a Red Ryder.
Read up on Jim Cirilo, Audie Murphy and John George. They would all take exception, and so would the men they killed with the pipsqueak rifle.
Amen to that last sentence; those guys would know.
Regarding reliability with 30 round mags...replace the magazine catch with an M2 catch...problem solved.