I purchased the GenZe last month from Amazon and just love it. Although it's rather generic and may not suit most folks needs it's been near perfect for me. I had no interests in fenders, lights and most other accessories so that was no problem plus it cost half as much as the Trek. I did buy new Continental Country Plus tires and switched out the saddle with a spare Terry Fly Tri Gel I had removed and stored from a previous bike but that's been pretty much it.
Performance has been as advertised with a 18-20 mile range using the pedal assist mode and getting a top assist speed of around 17 mph. Since I ride primarily on paved trails and park roads this is good enough for me. Even after 18 miles it still shows I have around 40% battery life remaining. My primary reasons for buying an e-bike was for hill climbing and winds in excess of 25 mph and it has exceeded my expectations with both. I realize it's Texas not Colorado but it has handled every hill even with headwinds with ease.
Out of the box I only had to attach the front tire and adjust the disc brakes and shimano gears then it was ready to go. I had no problem contacting GenZe with a few questions I had including the price of a second battery ($325) and the 18 mo. warranty.
Finally it weighs around 40 lbs without the battery so it's been easy to load in the back of my SUV using a pet ramp.