So I now have 6 magazines total. 1 that Ruger sent me, 4 that I bought that came in two packs, and the original it came with. Out of those 6, 2 of them did not malfunction at all at the range, the new pack of 2 that I bought had some feeding issues, and the one that Ruger sent had some FTEs. I ran the one that I thought I had isolated as a bad mag that would FTE and it ran flawlessly. So maybe it's not the mags.
The new mags had an interesting malfunction too. It extracted, but when it tried to feed the next round, it tried to feed 2 rounds into the chamber vertically, facing up.
All the mags are marked "Made in USA", and I'm not sure if anyone has ever noticed, but the bottom of the mag has a number stamped on it where you would push to remove the mag plate. The two that did not malfunction are marked #1 and #2, I had 3 that would double feed, all marked #3, and the original one it came with marked #4.