Update to this, I bought one of the 21 rounders just out of curiosity. Only used it once and it worked. I am actually reluctant to render an opinion on it, but it doesn't really seem "robust". But I wonder about if that is just decades of experience being used to something else. I watched one of the YouTube interviews from SHOT where the guy explained some of the drop testing they have done, and that they are molded from a specific polymer they specified. It could be the next big thing, but by it sure is different.
I am contemplating getting a couple of 17 round versions, and using them every week along side the factory mags and see how they hold up.
State Government Attorney | Beretta, Glock, CZ & S&W Fan
I have three ACT magazines, but I seldom use them.
I bought one of the 21 round ETS, just out of curiosity.
I really do not have any "need" for any more 17 round magazines, for a long while Botach would sell factory S&W (and Glock, at the time) for $20 if you bought at least Qty6. At that time the ACT magazines were not enough less (hard to beat $20...) to make it worth the deviation, though the three I have seem great.
And now the going rate for the S&W mags seems to be $29 at the lowest, and Botach offers the ETS M&P magazines for $14 (the Glock ETS mags are only $12).
And I am cousins with Curious George, and if now Pmags are the damn standard for the AR, why shouldn't a magazine be able to be plastic? And if it is plastic, why couldn't it be transparent, might the tinting even make it a little less strong? So I bought a couple of them, though I did order from Brownells for $18, because I get the free shipping through the Edge membership so it was net same as Botach (who were charging a reasonable amount for shipping, but it netted out the same).
I have a batch of six magazines I use each Sunday and I will start using these in place of a couple of those. Shooting nothing but ball practice ammo I am sure neither one of them will ever fail, but experimenting is part of the fun for me.
Update:
Well, not sure these are "bad" but I am probably not going to keep them and use them. The way the follower fits it is trying to get out in front of the feed lips and makes inserting an empty magazine funky. They also slide right into my 2.0 gun but seem tight in my 1.0 gun. I am really torn on these, because I am generally supportive of companies that develop stuff for smaller markets like M&Ps, but when I take a realistic step back if I take these out and use them then I will probably never send them back, and I am getting to the point where I need to start being more careful keeping stuff around that I spent $35 on that I know will end up in a drawer.
I want to be clear that nothing about these would not work, and they are probably a workable option for $14. If I didn't have a significant number of M&P-9 magazines I would keep them and use them.
At this point I plan to utilize Brownell's satisfaction guaranteed option and send them back. If somebody else wants to take one for the team and work them out I will send them along for $30. Lemme know, I will probably pack them up on Saturday.