Company I work for is in the market for a medium duty straight truck to accept a 24-26' box. Dealer nearby has a 2015 model Durastar 4300 with a Cummins ISB engine and Allison 2500RDS trans. Anyone have experience with these and have any thoughts? I have drove a Ryder Freightliner M2 with the same engine and it seemed like a pretty good truck, however it had an Eaton UltraShift trans. Thanks