Well here's some of the specs on the Allegro (copied from website)....Low miles at only 78,000 ( thats only 5500 miles a year) This Allegro is built on a super duty Ford chassis with the 6.8 liter Triton V-10 that produces 305 horsepower and 420 lb / ft of torque Plus has the upgrade banks power pack for more torque and horsepower.
I don't have the same on the diesel, maybe later today, but from what I found out this model came with either a 235hp or a 275hp engine. I do know its on a Freightliner chassis with air bags and air brakes
Mine now has a V8 460ci in it rated at 255hp and 405ft/lbs torque to compare.
Edit...Just found out the Coachmen has a 275hp engine. Dealer says it has some delam and some body damage and "above average exposure" (no wonder he avoided my questions) I'm headed out to lay eyes on it now so we'll see, but it sounds less desirable now.