Pressing down on the slide stop of Glocks will impart wear to them as the slide has a sharp edge (steel) and the slide stop is aluminum..
I'm not trying to be combative; I just want to sort out the accuracy of that information:
I've seen this type of advice/caution passed around on the internet for 10+ years but I have never seen or even heard about a Glock slide stop lever getting worn out due to using it by simply pressing down on it to release the slide.
I can't say how many mag changes I have on my extended slide stop lever (can't recall exactly when I installed it), but it's enough that I'd notice some wear by now if it was going to happen. Additionally, as I sit in my chair in the evenings, I typically practice mag changes for a couple minutes as I dry fire. I use the slide stop lever then, also without babying the slide. I just inspected my slide stop lever, and the black finish is worn off, but the metal itself appears undamaged. Here are the pics from 2 minutes ago:
I suppose if/when it does wear out, I'll spend the $10 and get a new one.