I have worked on Over 100 of the G&G raiders. One of my very own seems to do the trigger locking up even though not on safety thing and I have yet to rectify this, my best guess is that the actual lever the selector plate pushes can kind of get stuck sometimes. moving it around a bit might help, the little response issue has been fixed by me dozens of times, either the motor contacts need cleaning or the contacts inside the gearbox, should work good as new if they are cleaned up. As for that mosfet being recomended I own the older AWS raptor fet and I love it to death, 100% happy with it and is worth every penny you'll spend.