When I first started looking at MH's I quickly found out after driving several of them, I quickly found out that my "number one requirement" was going to be that it HAD to be quiet. So many that I drove were just awful. I couldn't fathom taking trips is a noisy MH.
You mentioned your first noisy MH was a Class A. I found that everyone I drove and all my friends Class A's where like driving a commercial bus in the middle of downtown Chicago! They were loud.
Class C's are not at all like the Class A's. It sits on a van chassie and IMHO rides and handles like a real nice conversion van.
Four Winds, V-10, E450.
Is what I ended up with because it was the only one that was quiet inside, Engine, no window leaks, and all cabinets completely constructed and made out of REAL hard wood which does make a difference in them not rattling. Cheap cabinetry rattles. Something to think about when you are looking for your next MH.