My last 3 motor kits were from the Rico Group. That's BGF, and Lucky Early Bird. Their motors are no better or worse then anyone elses china girl motors. That means pretty crappy out of the box. But I've learned to correct most of the shortcomings.
What I learned is the parts are the same. Only the quality of labor and assembly differs. All you need to do is take it completely apart out of the box, and put it back together correctly. Replace all the Chinses bearing with real bearings.
Doing so makes it easy to address performance modifications at the same time. I love my latest creation.