I tried BH and Bulls Brose also Ariel Rider.
I can say that brose is a good motor at the moment for cruising but not for hills. I feel the motor is kind of weak don't give enough torque. But hands down it is extremely silent and smooth .
So being silent and smooth isn't a major factory for a MTB but for commuting i will prefer Brose. I still advise to use Bosch at the moment especially for a MTB.
Shimano: This is a company if i have option will never ever use their products. They kill every small business and with their endless patents they prevent small companies to start-up. I watched a video a guy was complaining how much damage shimano is doing to bicycle market.
I am sure Brose will solve this issue as i talk with their engineer at Eurobike they told that in 2017 there will be a new software update which will increase the speed and torque of motor. Normally i wouldn't believe it but a company like brose who produced electric motors in millions of units, they have this capability. I think now brose is finding its path to understand what e-bike clients are looking for in a motor which is different from what car drivers are looking for in their window opening motor ....
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Brose's mid drive is rated at 90nm of torque.
If I'm not mistaken, that's the strongest name brand mid drive out there.