I installed the dual hotend up to the point where the instructions end now (so there are still some parts missing).
There are some problems I see:
1. The motor on top that switches the hotends "steals" lots of room in Z height, so the full 30cm are not usable more like 25cm.
2. The shrouds (?) of the cooling fans are too low so they touch the printbed before the nozzle, even if the hotends are installed as low as possible
3. Installing the printbed in the center of the frame (like written in the instructions) leads to the printhead not being able to print on the full X size so I had to slide it about 10cm out of center.
Did I something wrong?