We had Metrotec chassis with 210 Phasers and the 180hp Benz were more reliable and about as fast! We sold most of our old buses for motor home and I would hate to buy one with a phaser. Who's bus is it?
I knew the owner before they sold out, it should be better than the ones we had! We had to change the gear shift cables as they were wearing out to often with all the gear changing in the hills. An RG230 Hino feels like more than 20hp difference to the Perkins.
With these motors you are forever changing gears so it is most likely that everything between the lever and gearbox will be worn. We had the same with DT466e 250hps and they would be still going today, the Phasers was apart 3 times in 10 years.