I think (could be wrong), that a 254 doesn't have the mechanism on the back door that makes the 3 top rollers come down to help form the centre of the bale. they're fixed instead.What’s the difference between a rollant 254 and a 255? There seem to be plenty of 255’s about but not 254’s. Is a 255 a reliable baler? Only looking to do a few hundred silage bales a year.