Trail Cruiser problems

Looking at a very nice 2005 Trail Cruiser, has the perfect floor plan for us so we're interested. We also like the fact that R-Vision trailers are really pretty light (we had a 2000 Trail Lite for a short while). I noticed that the floor outside of each frame rail slopes down toward the outside wall. Knowing that R-Vision uses "sandwich" panels and no studs or joists, it would seem that this might be a common problem. It doesn't bother me too much unless it becomes a serious matter, mighten it?