I started out thinking like you. the Home depot rings were rated at 800 plus pounds. Got to be good enough.
Then, one day on the trail, when the trees were far apart and my hang was dragging on the ground, I tightened the hang a bit more several times and those steel rings peeled like a ripe grape. That math post a few back is right on!!! I had to hoof it another 5 miles to reach a shelter. Made it at 9pm.
Descending rings cost a bit more and UPS makes a few bucks too, but they haven't let me down