Hi ! Just to keep you updated, the construction of my new layout (2x4 N scale) has begun ! After many many days of relexion, I decided to go with NO roadbed, for some reasons: 1- On my previous layout I used foamboard as roadbed, and it was WAY too high ! 2- The layout is build on a 5/8" plywood topped with a 1" blue styrofoam, so I don't really need any sound-deadening. 3- With NO roadbed, I can still achieve the roadbed profile I wanted. 4- I tried it, and the results are far more impressive than on my previous layout: Please note that on this test picture I glued the track directly on wood, but on the layout it will be glued to styrofoam.