The only real weakness of the 90 is it is striker fired, and that is about the only thing to get out of whack. To check, make sure it is unloaded, slam it shut a few times to make sure the sears don't trip. Then bounce the butt on a carpeted floor to see if that will set it off. Do it with the safety on and off. They were made from .410 up and I think a few in 30-30. Shoot and enjoy an under appreciated American classic.