I have found similar foam to WS roadbed at Home Depot. This material is translucent blue and about 6-8 inches wide...and cheap! It seems to work great with flex track since it cancels out small imperfections in the sub bed. It comes in a nice width to more than cover dual track roadbeds...and super easy to trim around corners. My only concern is static electricity. Is there any link between foam roadbed and increased arching?