I have seen a number of folks show a preference for the metal follower. My collection of 52 magazines might be right at 50/50. That’s a clue that I make NO distinction, and have never seen a difference between the followers, ever.
I have gotten some mags that don’t feed well — my method to fix them has been to take a 52 magazine that I am dead sure certain feeds well, make note of the feed lip dimensions in multiple places and then (carefully!) bend the feed lips of the troubled magazine until it too functions flawlessly.
This has worked well for me.
If you look under enough rocks for 52 magazines, you will eventually come across one that has been altered to fit more than 5 rounds. This is done by extending the side slots by which the follower is guided. I don’t happen to own any, but I believe that extending the slot at a slight LESS angle is the preferred method of making these work.