USA AR15 mags are crap. I'd set them up at 100yds and shoot them while handloading my AR before I stuck them in the magwell of it.
Stay with USGI mags and you can't go wrong. You can find them for $15 each or so and I doubt you can find the USA mags any cheaper.
You might be able to find some USA mags that work, but the large majority of them have problems. Even if it only jams on one round every two or three magazines, that is too much. Surplus mags are by far superior.