PTW 100%. once tack'd you don't need to worry about it. I have two, the first one had a tack'd motor put in it 2009, hundreds of thousands of bb's since then, opened it a couple seasons back for a checkup, just needed lube. The other is newer but same deal, no issues. They work, I don't need to strip them down every month to fix them. I don't play as much as I once did, but they require little maintenance, a wipe down and the occasional re-lube.
Run good ammo and you won't have feeding issues. I've never had issues with my bolt stops other than occasionally catching it on gear but not a big deal. Still worth the price imo, been running dubs for 11 years, only ever had one fail, and that was my fault for playing in a 12 hour downpour (Claybank 2) not many guns survived that day.
"Those who have long enjoyed such privileges as we enjoy, forget in time that men have died to win them"
Franklin D. Roosevelt