Assuming good tires, I'm guessing that those who had issues with dynamic balancing had one of a couple of things wrong:
1. Shop used too much or too little for the application.
2. Shop didn't install filtered valve stems, and owner didn't do their due diligence to research and understand their advantage.
3. Shop used Equal, and used an excessive amount of lube on the beads, slopped it inside the tire, etc., causing the Equal to clump up.
1985 Gulf Stream 34' Sun Stream
1997 Newmar Mountain Aire 3757