I've got a few commercials with self cleaning glass. Tread carefully, because if you damage the coating you will be liable for re-glazing (at least on commercial, domestic probly dont care?wont notice that much) and your insurance wont cover you. Managers are sometimes very anal about it because its like twice the cost of ordinary glass and they think they know it all and window cleaners know nothing.
WFP is usually fine but DO NOT UNDER ANY CIRCUMSTANCES USE A SCRAPER. That WILL damage the coating. Also make sure only the bristles touch the glass, never the brush head and NEVER the jets in the brush.
Does it work? Hmmm yes to be honest it does, the water tends to sheet off the glass rather than form droplets, which does make it easy to clean. But because you have to be extra careful it takes a bit longer, so charge more. Also charge a bit extra because they have had the audacity to install it in the first place.