Nice to have factory reliable 140 and 170mm mags for comp pistols and PCCs, without spending $50+ per mag/extension, or using a less than reliable aftermarket mag. I have a lot of 33rd mags, a little clunky to reload, or shoot prone with, love my Magpul 21rd mags, much quicker handling. I like these, and hopefully work with all the newly adopted PCC division length restrictions.
I’ll give you that, but I’ve got 2 PMAGs and 5 of the Korean mags for my Glock 17. None have had hiccups (and two Korean 35 rounders, 33 with factory +2 mag plate extensions).
But I’ve read enough reviews to know that some people have had bum mags.
I don’t compete and my limited experience most pistol mag pockets will fit a Glock 17 mag and no more. A few of the carries I have can just barely get the 17 mag I have that has a +2 baseplate on it squeezed and with the Velcro holding it...but it isn’t super secure.
The +2 is the ready mag and then I have a spare regular mag that either goes in a pocket or in to the holster’s integral mag pouch and the holster clipped to my belt or pants if I think I have time to dress up for uninvited guests.