Other that custom Prevost based buses, my personal ranking for Class A motorhomes.
Foretravel & Newell, quality build, top quality components, manufacturers that back their coach and will upgrade/re-condition them. Down side, even an old ones aren't cheap compared to mass produced coaches their age.
Next tier would be Country Coach, Monaco high end, Travel Supreme (now Entrega) and American Coach, but none of these companies really exist as they were 10 years ago. All have suffered through major turmoil, restructuring and/or change of ownership. But quality was there.
Winnebago, Newmarr* and Tiffin* come next, good quality coaches that are mass produced with decent track records, overall. These companies build entry level to some higher end Class A's
One's I would personally stay away from as a novice full-timer, Fleetwood, Thor (Damon*, Four Winds*, Dutchmen), Forest River (Coachman*, Georgie Boy*, Sportscoach*), Alfa, Alpine, National RV, and R-Vision*. Some are gone, many consolidated, some haven't been known to come to the plate when problems happen.
* We or family members have owned products by these companies