I am familiar with W/S roadbed its very similar to topper or camper tape I think the only difference being topper tape has a self adhesive side. I will never use cork roadbed again, it drys out and cracks and crumbles if you like it and have no issues with it then more power to ya.
Flexxbed appears to almost be like a thick vinyl and very cushioney if thats even a word making for better sound deadening.
I'm installing the Woodland Scenics foam as we speak. I use the 24 foot rolls. It bends easily and can be put down in a continuous run without any gaps. One roll is now down and another to go.
Springfield PA
Any one ever use Flexxbed vinyl roadbed? Just curious how it works, looks interesting but then again so did first class on the Titanic