Two years in the Making!
We viewed, drove, studied, questioned, rented Class B vans for two years before deciding to buy a Cochmen Nova. My short comparison, with focus on Gas powered / Lithium-based coaches, is as follows (overall build best- worst):
Gretch are excellent in all areas, but you have to spend $$$ and they are diesel.
Midwest Automotive Designs / American Coach are also very close to the Gretch quality for less $. Most are also Mercedes, but some are Fords (a tiny bit of Rams). However their dealer network is slim and our attempt at correspondence with the company was not answered.
Pleasure way. Great overall quality. Lithium currently lags other's capacity - Dealer network is slim in US.
--- Coachmen (see below)
Winnebago Travato is of similar design to Coachmen, and has the best Lithium battery system, but are overpriced -- pay for brand not quality.
Roadtreks have a great history, and the best floorpans, and an amazing amount of storage but their Lithium battery system is outdated and cumbersome.
Every sample we looked at from Thor industries (Ethos, Thor, Jayco) had quality problems; sometime parts literally falling off when viewing them in the showroom. (We did not look at Airstream as they were all diesel.)
Now as to Coachmen. No one, really, no one has better quality cabinetry, there is no real comparison short of custom made. As to over all build quality, Gretch,MAD/AC had them beat but IMHO not worth the extra $. For lithium; Coachmen has the 2nd or 1st best designed systems. If pleasure way had the Lithium design of Coachmen or Travato I might have gone that way. One great feature of Coachment Lithium Models is that batteries, fresh and black are all inside. Leaving only gray (with heating pads) out in the elements. While is is near impossible for a van to be "well" insulated. I don’t believe anyone has better insulation (sound and temp) than Coachmen (although MAD/AC would not respond to us about it.)
The real differentiator is the Dealer support is amazing. Nick Recchio (the head of CM class B's) Answers questions on YouTube, comes to Rallies, gives out his email address, and his staff is just as available. As an example; I saw Nick climb a ladder and zip tie a customer's awning, because there was a recall for a deployment defect. - Not a Coachmen recall, an awning company recall. That is service! As the previous post mentions there are some wonderful Facebook Nova groups (if your into that) who will attest to my ravings about customer service and also provide valuable assistance to issues you may have.
I hope this helps, but my best advice is to check them out yourself, even if it means travel, and spend a good deal of time looking underneath and behind the all the "shiny" bits.