STEn Conversion
I had Wheatley do a STEn conversion on my M11\9 a couple of years ago and it is very reliable. I have about a 10% miss ratio with surplus mags. Just buy a couple of hundred and about 180 will work fine. Just FYI on some you have to crush in the mag stops a little to fit in the mac mag well. If you look you should be able to find STEn mags for a couple of bucks each.
Brkdnc, I have never had to tweak any of my mags, and I mostly use the same 40 over and over.
best