Hi TH,
I purchased one a few months ago, and balanced my BJ8 wires. I machined down some ABS pieces from Home Depot on the lathe to center them on the balancer due to inconsistent results. So far, its worked well as I don't have any issues with balance, but I did have the drums and disks/hubs balanced at a speed shop to ensure the wheels would be independent of the other rotating parts. One drum was really out of balance, and the guy had to dril as well as grind on the OD of the drum. The thing with the HF balancer is that there is alot of friction in it, so I had to bump the wheel on differnt quadrants and watch where the bubble would end up and balance the tire/wheel so that it ended up in the same position with respect to the ring around the bubble....it takes a while to do a wheel like that. I greased the pin too, which helped a little.
The Lotus, however, with 13 inch wheels wouldn't balance as well, so I bought a spin balancer off Ebay, which really did the trick.