Road force wheel balancer simulates the actual road forces your wheels/tires/car will experience at speed with this roller thing, and the software and process are more thorough and sophisticated to determine and resolve specific problems with your wheels/tires.
I actually think - unless you have out of round or bent wheels - “Road Force” balancing is a waste of $$$.
The way “Road Force” wheel balancer is supposed to work - it puts a force on the wheel that is supposed to simulate the weight of the car as the tire rotates. If the machine detects a high or low spot on the tire, or a hard spot on the tire, it tells the mechanic to move that spot to a certain relationship to the irregularities in the wheel.
Problem is - when I’ve had it done - and stood there with the tech doing it - he couldn’t find anything out of round or out of true on my wheels to match up with the spot the “Road Force” determined was needed. So - it ended up being a standard high-speed dynamic balance job.
About the best wheel balance you can get is where the wheel is spun on the car - Hunter used to make a wheel balancer like this, and a few other companies. That balances the entire assembly - the wheel, tire, brake rotor and hub assembly. Unfortunately - not many shops do this anymore - all the old techs who knew how are long gone, everyone relies on the computer to tell them when it’s right.
If you do have a bent or out-of-round wheel - then Road Force wheel balancer may be helpful, if you have a badly defective tire on that rim. Then it might be worth the $$.
I had a road force wheel balancer and it was completely useless. I mean the machine looked cool and it seemed like I was getting a perfect balance but when I drove at higher speeds it still vibrated. They ended up throwing the wheel on a regular Hunter wheel balancer machine and were able to balance the wheel perfectly fine that way. My wheels ended up having way too many weights on them from the road force wheel balancer.