We also have windows with sloping surfaces on the side of the conservatory.
The W1 Pro works perfectly there.

I would rule out this model because there is now a successor. However, my experience with it is that it struggles to keep the track even on straight, very long windows, especially if the cable is not 100% strain-relieved. I suspect that there are more suitable models for your application, such as lighter ones with two round wiping pads that can also clean for short periods without a cable. I would do a little more research.

Doesn't work on my roof windows, only when the surface is vertical ... had the same idea, unfortunately not. Nevertheless, the robot is a good help - even with the roof windows.