I have several gen 3 G26 and G19 magazines (those with no ambi mag release cutout). Several came with #5 followers, most came with #6 followers. I also have several gen 4 G26 and G19 magazines (those with the ambi mag release cutout) that all came with #6 followers. The gen 4 mags are also a little longer (maybe 0.1") than the gen 3 mags due to the need to fit with the largest gen 4 grip panel. I also see the newest gen 5 magazines come with orange #6 followers for easier round count identification.
Is there any reason to swap out my #5 followers for the latest and greatest #6? Any reason not to? I have not had any feeding issues with either follower using my cary or training ammo, but there are for more ammo brands and bullet types out there that I have not tested, and Glock went from the #5 to the #6 for a reason.
For that matter, I could swap out all my followers for the orange #6.
Again, I know I don't need to, my question is if there is a valid reason to do it anyway. Similar to updating a gen 2 Glock with an LCI extractor (the original works, the newest works better).