We owned a 31 foot Keystone Springdale for 8 years and we were "pretty" happy with it until receintly. The floor plan just did not work for us any more. But as far as the durability of the camper, we had very, very little problems with it. After a couple warranty issues, it went in for repair only after 8 years to have the brakes fixed. (a wire rubbed and was causing a short), replaced tires once, and changed the battery after 8 years (and then we sold it ... arr... how stupid).
See my "profile" (on the left) and you'll see a photo of it. It served us very, very well!