We have a test ride in mountains today, I also ride a bike in M size. I'm not tall, the bike to me is a little big, but the seat tube height is OK to ride on.
We ride in mountain and try to ride in the area without good road condition or even without road. I think there is few bike can ride in the terrain. Thanks to the good power motor, throttle to help start in some condition and 6km push mode by pressing "_" button also helps much when we reach somewhere there is no path for riding. It is really a good bike to conquer all kind of terrain.
To my experience, there is not many bikes can ride in all kinds terrain or it may require a good capacity and skills to the riders. But to AM1000 rider, it will become more easier.
Below some photos we ride in mountains today. You can see I'm a little woman. : )
Later we will try to upload some video for you have a look.