I went through several brushes today, swopping from dual trim mono to dual trim flocked to scrub snails trails off. I found the flocked almost impossible to move sideways and very clingy vertically (maybe it's a second quality). I went back to the later extra splayed dual trim later in the day and still wonder why the bristles are not made denser.
Last job of the day I accidentally fitted an original no splay MK1 dual trim mono - my god that's one fast and accurate brush! It really zips across the glass.