Where worked we had one Marathon, an E290 engined full sleeper, decent enough lorry that from memory wasn’t all that different to driving a Scammell Crusader, for some reason i recall it having a Spicer splitter box but that might have been the one Roadtrain (again E290 engined) we had, so take that with a pinch of salt it might easily have been a standard Roadranger.
Due to axle design it didn’t have the tall gearing of the Sed Acks, so wasn’t especially economical at speed, and like the Roadtrain the cab rotted like hell, but then so did everything with a steel cab…and no the foreign motors weren’t any better for rust either.
For pure driving pleasure i actually preferred the Buffalo, which with its fast revving engine and perfect matched gearing could make good progress and handled better to boot being more agile.