We had a '07 260FB and LOVED IT!! That's a travel trailer not a 5th wheel, so I can only comment on the build quality of the line...
...It was built VERY well and except for a missing fuse in the converter at delivery, it never gave us a single problem.
We had the cold climate package - used it in the Sierra Nevada with no issues in the cold.
Last year, we sold it to a family that was using it for fulltiming and loved it too.
Our Denali was HEAVY for it's size due to the hardwood and extra insulation, but I towed with a 1 ton Diesel truck - no problem.
The most amazing thing to me was that the trailer was in storage impacted by the 2007 Witch Creek wildfires that hit here.
October 2007 California wildfires - Wikipedia, the free encyclopedia
The trailer did not suffer any damage because of the fully enclosed belly, insulation, and overall high quality exterior materials. The house at the front of the storage area burned to the ground and 4 other RV's next to our Denali had burned sections of roof, walls, or melted holding tanks from blowing brush, but there was not one mark on the Denali!
If there was Denali Class "A", I would have seriously thought about buying one when we upgraded!