I have been using a second hand Haibike with a very old Bosch motor. A local dealer has a new model but it has a Yamaha PW-ST motor and I am really struggling to find a review of it, or a bike with it fitted. I know that a test ride will tell a lot, but a couple of laps of their parking lot is only a guide. Bosch seem to have the market pretty well sewn up, so perhaps it is a mistake to go for one of the minority players, but it is a good brand and Yamaha motors used to have a rep for long term reliability. Can anybody help? Any experience out there?