I got my new brushless DC servo working using my custom controller I posted about a few weeks back. As hoped, the tighter control I'm getting out of the new steering mechanism has resulted in much better vehicle stability at low speed. I'm now good to go down to 4 mph, which is when the auto balance kicks in; it used to be a little shaky below about 8 mph and only smoothed out when faster than that.

Low speed and off pavement test run