You do need a good brush for a rinse bar though, the bristles can obstruct the rinse if the splay too much.
I have been trying lots of different brushes and have been struggling to find the right one, I even bought a constructor brush but the rinse bars do not cover the entire brush, and theyre heavy and awkward so its on ebay.
I bought an x line dupont, the ones with the orange inner bristles. I didnt use it much as the bristles were long and a bit awkward for my style. I got the scissors out and gave it a haircut, I cut the out trim down to the same size as the inner trim and I have to say its friggin awesome like that. No splay, super aggressive and light. I love it!
Sometimes you have to take whats on the market into the shed and make it your own. The x line now is ideal, it was only 209 gramms before I cut it down, its probably only 190 gramms now. It still gets into the frames and corners no problem and its all bristle tips on the glass so it shreds the muck.