I have a bunch of the 10rnd Wilson mags. They have been pretty good. The follower had to be trimmed so that they would load easier. I was hoping someone made a 15. I guess the single stack is to unstable at that length.
have not heard of or seen anything more than 10 rounders for 9mm 1911.
I have a metalform 10 rounder -- works well - looks the same as Dawson Precision mag.
I seem to recall seeing some crazy long magazines for a full auto 1911---even longer than these...this isn't what I was thinking of but it is what I found...