I had a bit of gear whine in one of Doug's steam engine conversions, but lubrication of the gear train in the transmission to the lower drive shaft helped with that. Strangely, the noise is at low speeds only; at normal running speeds, all the engines that he rebuilt for me run very quietly.
My big MG Rio Grande L-132 (a 2-8-8-2) draws less than 0.50 amp at around 10.5 volts pulling 30 free-rolling cars at a stately speed. Also, it will creep along very, very slowly without hesitation, when necessary, as will a USH L-105 that Doug rebuilt and painted about 10 years ago.
I agree that the quietness and simplicity of a toothed-belt design has a lot to recommend it. So far, however, Doug's drives have been "bullet proof" in my experience.
