I know 3 people who have them and like them. The magazines are tight from the start so they can malfunction when loaded with the full 30 rounds until they break in.
An option to break in the magazines is loading the full 30 in both mags and leave them loaded when not in use to let the springs relax a bit while they rest.
One of the guys just loaded 25 in each mag until he had 500 or so shots through it and them loading with 30 wasn't a problem.
