I bought my first M1 Carbine because I had a service rifle match on SUnday, but an open morning at a range where they were also having a tactical rifle match on Saturday. They had a "battle rifle" class as well as a light rifle class, and I had the battle rifle covered with my M1A, but I needed a light rifle.
Consequently, I bought a Inland M1 Carbine in excellent condition (you could still find them in that condition in the late 1980s for about $200) at a local gun shop along with the only two boxes of M1 carbine ammo he had - 50 round boxes of surplus Lake City GI ammo ($5 each) - and three new in the wrapper surplus 30 round magazines.
I used 10 rounds to zero the rifle and check the sights out to 200 yards and then loaded the other 90 rounds for the match. I got some very derisive looks from most of the other 20 or so shooters at the match. Most of them had AR-15 carbines or rifles, one had an HK93, and a few had SKSs - which were available for about $80 at the time with a case of ammo selling for the same $80. Many of the AR-15 shooters were sporting muzzle brakes and other gadgets, even before that became the norm on an AR-15 and they regarded them selves as the serious contenders.
The target ranges varied from close quarter combat out to 250 yards - which is almost perfect for the M1 Carbine. I ended up winning the battle rifle class and I placed second to the guy with the HK-93 in the light rifle division - beating each and every one of the AR-15s. That was very satisfying all by itself.
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Currently I prefer the 15 round magazines and I think they are both more durable and more reliable than the average 30 round magazine.