I have owned 3 turntables in the last 15 years as follows:
Rockport Capella 2 (belt drive, medium mass platter, low friction bearing, low torque motor)
Brinkmann Balanced (belt drive, high mass platter, low friction bearing, low torque motor)
MA1 (rim drive, high mass platter, very high mass / friction bearing, high torque motor)
I designed the MA1 and outsourced the manufacturing of this ultra smooth, ultra quiet high end turntable. When compared to belt drive turntables that I have owned or heard, my MA1 has the PRAT and energy that very few turntables have. I decided to go with a high mass platter and high friction bearing for 2 reasons: 1. the high mass platter has high inertia which helps the platter move thru transients with less adverse impact 2) the high mass / friction bearing keeps the RIM drive motor engaged with plenty of torque such that any perturbations caused by the stylus will be easily overcome with little to no impact. Using the rudimentary wow/flutter test provided by fickert on the ipad, my wow/flutter measurement is less than 0.01%. I firmly believe that a high torque motor, high mass platter and a high friction / high mass bearing is a very good way to keep stable speed with excellent PRAT.
Thanks, Pat