We have a 2013 Diplomat 43dft. Our MAxxforce 10 with 405hp and 1,250 ft/lbs of torgue has just over 13,000 miles on it. The only problem we have had so far is a faulty cam position timing sensor. Otherwise this engine has performed and worked as expected. When I did a back to back test drive compared to a Newmar with the 8.9 ISL Cummins, I honestly couldn't say one preformed better than the other.
So far we are really happy with our coach and have lived in it fulltime for over a year. We probably had the normal amount of new coach problems. Mainly small items that we're easily corrected.