oh my word ..this 20.8 fw is a GEM. This is what I have been waiting for after trying all the fw from 46.7, 46.8 and 14.6. The power distribution is similar to 46.8 drawing about 4A at PAS1/9. No brutal ramp up of 10A as detected in 46.8. It has a slight ramp, I believe about 5-6A just sufficient for a slight push when stomping the pedal. Range is marvelous possibly better than 46.8 as there is no overun when pedalling is stopped. This is very usable for technical trails with roots, ruts and severe undulation. No sudden lunging or wheelie when press hard duri ng pedalling transition. I would urge those who does hardcore technical riding to upload 20.8 on your M600. It will probably give the M510/M500 13A or possibly the latest Bosch a run for its money. Sadly, this will not be suitable if your rides are mostly fireroad, tarmac, commuting, pulling a sledge, touring and other similar mild terrain. Use 46.7 instead.