I have used the future of water fed poles today and not one manufacture has made it yet.
I held it, used it and put it through its paces today. A pivotal brush head ( bit like a wag tail) that uses the tubing to the sill brush as a spring. The sill brush has been modified with rows of softer bristles and two rows of firmer bristles at the bottom of the brush head and a row of bristles removed between the soft and harder bristles.
I have pics and video of it in action. That window over the conni roof? No more struggling at an angle and hitting the brick work. It hits square over the frame and glass.
I am hoping to show you how to DIY it step by step......