I have one and its an OK brush.
The one thing I don't like about it is that when transitioning from glass to frame you either have to lift off or bash the frame.
My favorite brush has now become the flocked extreme, its a very easy brush to use and gram for gram it by far outperforms any brush for scrubbing ability.
I am considering cutting off the bottom row of bristles as its a little extra weight and I cant see the benefit, you only have to maneuver the brush sideways for the sills, I've never had a problem with them.