Used it on new and old leadedlights, and it works very well, flows over the glass quite nicely. Very happy with it.
Has anyone noticed, that at extreme angles over flat roofs, the brush seems to grind to a halt when you go over a certain angle? I've had it only with beading windows today, so that might have had a lot to do with it, but I can't remember if my old Ionics did that too. Interesting.