Build quality by same manufacturer: Class A vs 5th vs TT

There is a big different between what a manufacturer makes. I would look at a trailer, a class "C", a class "B", a gasser class "A", then a DP "A", and each will be built to completely different levels. You can tell this by how the cabinets are shaped, the dividers separating cabinets, doors, screws versus staples, and so on.