I have a freedom gunworks built by Bobby with the steel grip. (Very similar to the thunder series only mine is a short dust cover). My gun started off rocky but now i love it. The issue that I had in the beginning was the magazines that i had were all out of spec and causing feeding issues. I got the magazines tuned and the gun has run flawlessly since that time for the last 2500 rounds. I would buy another one (now that i have tuned mags)