If you are comparing these two...
Haibike comes out ahead just because it is spec'ed for a true All Mtn experience. True eMTB involved riding highly technical terrain and specs like dual piston brakes, dropper seatpost can be very handy. The BULLS is a very nice bike but it not spec'ed like Haibike. If you are not riding such technical terrain then it doesn't matter. There are people who strongly prefer the smooth assist of Yamaha PW-X motor and there are others who think highly of the Bosch CX. Both motors provide good amount of assistance over wide RPM range. The PW-X provides more torque than the Bosch CX and it is smoother than Bosch but you need to be careful shifting as it lacks the shift sensor.
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I would recommend a test ride because you learn a lot more that way.