2010 Keystone Montana 3585SA 2010 Keystone Montana 3585SA Montana?s luxurious new decors and easy living features provide the comfort and luxury consistent with Montana?s reputation being the #1 selling fifth wheel in North America. None of the details have been over looked or forgotten. Plush residential furniture, state of the art remotely controlled electronics, and solid hickory cabinetry only highlight this fantastic 2010 Montana!