I am always a little hesitant when buying inexpensive tactical gear. I have, however, learned that a low price doesn't always equal a cheap product. These mag couplers do what they are supposed to do and they do it well. It is a simple design and once installed, gives you a secure feeling set of mags. They have worked great for me on several sets of 42rd. stainless mags as well as some std 30rd. aluminum mags. Also, I do not think these are the optimal solution for pmag users. I use couplers specifically made for pmags but, I do believe these would work in a pinch.
Pros: Lightweight, Inexpensive, Does what it is supposed to do...
Cons: none at the moment
This review was written in the old system and had content requirements that are different than reviews written today.