I like my TF Goliath and TT 10 +1 extension. I also have 2 40 round ETS mags that run flawless in all 3 of my PCCs. I also have a MBX mini that will not will not run in without a feed issue every once in a while. I've tried it on 5 different Glock mags, a Korean mag and a 31 ETS. It worked the best on the ETS. I've called and emailed MBX and they said to run it on the ETS. Wasn't the resolution I was looking for. So I will stick with TF and TT.