so what is the best balancing method

I agree, with Johnny, a regular spin balancer will do just fine for your situation. Yes Im sure the road force balancers get it almost perfect, but your not in that super critical area such as going 140mph plus, to need it that perfect. Discount Tire, Tires Plus, Walmart, anyone that sells and installs tires can balance them for you.

I do advise against the balls/marbles, liquid in the tires! My brother had a shop balance his tires with those balls and it was fine from a standing straight start. Anytime he went around a corner from a stop the tires where ridiculously out of balance. He would have to pull over on the side of the road and start out straight again.