Ewan
Vikan make brushes for Vehicles, windows and floors, if you can make the best brush in the world for vehicles, you can make more than a good enough brush for windows
What qualifies you to your opinion.
I have used every brush on the market, and still come back to Vikan, nothing comes remotely close to the new Vikan
I can show you photos of useless brushes including curled up Ionics brushes, I can even show you some rubbish square vikans, I have got about 20 redundant rubbish brushes.
Just try the new Vikan, you just might be amazed.