I've never understood the desire to have a surface tension agent on a car windscreen. I'd rather have the water sheet in a a way I can see through it than be all beaded up in between wiper swipes. As far as I'm concerned, it's awful stuff to put on windshields. I'd rather have a sticky silane rather than a slippery one. Different strokes for different folks, I suppose.
We're getting a little off topic but nanotechnological coatings cause the water to sheet not bead by filling in the small imperfections in the glass surface that water and dirt can cling to:
Not my vids:
That said on windscreens I prefer wipers! Some coatings when wiped definitely smear and even for those that don't, personally I think a wiped screen is clearer. Never understood why people don't want to use perfectly good wipers! That said these coatings are good for side windows and may help CCTV although I stress again the latter is an unknown element for me.