I've tried bracketless wipers on the bus, didn't work for me, (wouldn't
conform to curve) but are fine on my car.  Blade lengths on the car are 21
& 19, in my experience these will also fit the bus.

CR blade tests, Valeo 600 & Rain-X latitude came in at 1&2, next, Anco 31 &
Michelin Rainforce 3&4, which are also best buys.

  Every model was excellent or good to start, the only model better than
fair after 6 months was the Rain-X model.

YMMV.
Geo/ATL