We do a lot of properties and that self cleaning glass ( in our opinion) is a load of rubbish. It must be bloo** clever stuff to get rid of huge bird poo splats without even touching it. It's a bit too reliant on us having continuous wet weather. Problem is people really want their windows at their cleanest during the Summer when ( apart from last year) it doesn't rain much during April, May, June, July & August.
And it's also a bugger to clean, has a sort of film on it!!
There, i've had my little rant!!