I just wanted to give my two cents here, as I have been keeping my tapco mags loaded for some time now and I have a few experiences I'd like to share. I may update with pictures later if I get around to that
but for now here's what I know.
1. Keeping your Tapco mags loaded will stress them to the point that they will no longer fit into your rifle without what I consider "excessive force".
2. If kept loaded at full capacity you will loose some rounds off the top as the mag stretches over time (I have found about half a dozen rounds loose in the case in which I keep three loaded mags). Actually, I had a few that were downloaded a round or two and they still managed to lose bullets into the bag eventually.
3. After you manage to get the flexed mags seated into the mag well, they still function (which is good)
Tapco, I submit that your mags while pretty darn good, could still use some work. I continue to use them, but am now hesitant to leave them loaded (which I'd really like to be able to do). Perhaps a dust cover (similar to the magpul design) that relieves the pressure off of the feed lips for longer storage capabilities or an extra reinforced mag body of some kind. Until this is resloved however, I am replacing my go to weapon with something else.
Thanks Bill for your time and dedication in keeping our weapon choice ripe with options