I have a Coachmen SportsCoach (2013 385DS).
It has the ISB 340 hp motor. I don't care that it is "not sleeved" as I will never keep it long enough to see the benefit during a rebuild!
It pushes the coach nicely. Can I do 100 mph up a 6% 3 mile grade? No. Will it get me up and over? Yes.
I get 10.5 mpg hand calculated (miles driven / gallons used).
As far as quality... My coach came with some really nice amenities for a "lower level" coach.
Polished tile floor throughout
Dual Pane windows
8kw Gen
Outside Entertainment Center
Solid wood door cabinets
Auto Leveling Jacks
Rear and side cameras
17' Power Awning
Full width basement slides
I have had no issues with the quality of the build... I have had some minor issues with both the Cummins engine and the Freightliner chassis... both resolved quickly.
The cost of my coach was at least half of what a "higher end" coach would have cost. Funny... I don't see the people in the high end coaches having double the fun.
To each his own.
Mal