He's sending me one and the reason I want it is so that I can stay out longer cleaning windows before the water runs out.
I am finding that all the small improvements I make to my work add up. When I went hot (i was the first to DIY on this site to my knowledge) I thought all i've got to lose is £300 if it doesn't work. But it did work.
The electric reel was an £80 gamble for the drill, but that paid off too.
Peter's brush, if you tried to do it yourself, would cost a fortune in both time, parts, and sourcing. At £69 it has to be a bargain.