Okay, I watched the full video. I believe that the bike probably is a 750-watt nominal motor, but the battery technology will not support the 750 watts. Probably only 500-600 watts max. A higher end battery would deliver better performance. Expect about 20-25 miles out of the bike before the battery cuts out. This is pretty much a throttle bike and even throttles above 20 mph max for class 2. 20 lb of air in the tires is too much. More like 15 will deliver a better ride. The 20" wheels do not roll over things very well so stay away from chuck holes and curbs and off road. That stem is small and would not help at all in rolling over rough stuff.
It's really hard to know if the bike will deliver the goods for you. Great bike for RV campground.