I have a 742 that is 40 years old that is still shooting well and killed two deer so far this year with. My BIL has a 740 that is obviously older and still is shooting fine and taking deer also. My BIL's brother has a 742 that has had problems, but he doesn't clean it.

Semi-autos require a little bit more care and maintenance because they have more moving parts than say a bolt action. If they aren't maintained, they will wear out quickly.

I had a BAR in 7mm RM that I traded a few years ago. I wish I had it back.

With that said, if I was going to buy a new rifle, I would probably go with a pump action instead of a semi auto.