Mike, darned if I know what breaks on ChiCom Clones, nor will I ever know from personal experience.
But after maybe 60,000 rounds through divers 870s with exactly two parts breaking, I know how long they'll last.
One of mine was made in 1950, given to me in 59 for Xmas. Done everything from trap to 3 gun to investing in venison futures. 10-15K loads without a hitch. Now my house gun.
There's another here, made in 1955. A couple thousand rounds fired since it was purchased two years ago. Glitchless.
A couple more here have up to 15K on them. I figure I'll have to live about 300 years to wear all 6 out. Wish me luck...