If you want a washer and dryer plus that big refer you will probably have to go to a 5er. If that its totally out of the question then you my have to make a sacrifice.
Airstream is reputed to be one of the higher end TT's, I can speak for Jayco. While they may not be considered "high end" you won't find particle board in the cabinetry and it starts out with a two year warranty, one of the best in the industry.
Let me suggest this. Talk to an independent RV repair facility and see what say are the most commonly worked on vs. the least and what or who they think are a good build quality. I would ask several to see if a consensus could be developed. Just a thought, FWIW.
