I must admit that I didn't look at what bearings were in the motor.
I've been running quite a light tension on the belt - this small v belt is superb and doesn't slip and I ordered 2 belts at the time and have never had to swap it over.
The noise levels dropped when I went from plastic to steel gears, however, it was still a very noisy mill.
With the gears though at low speeds you could feel the backlash in them and the resultant impact on the cutter - not sure how much effect this has on the cut, but it did grate on me.
The belt drive is extremely quiet and really nice that you can back off the tension even further to allow some slip if you need it.
Best regards, Nigel