I had a very comfortable bus ride from Krakow to Warsaw for 7 euros a few years back. Each seat was able to lean back really far and still you weren't bother your rear neighbor. Each seat also had their own iPad-like-device with games, movies, music and internet.

Now Poland does not have many highways that are of good quality. But the ones we drove were good enough to sleep on. Also the toll for cars is really low (I believe 3 euros).

I'm willing to pay an extra to be able to lay down flat down but I really do wonder what surplus is added due to the stabilizing tech. I believe it's only applicable in a country such as the USA, where the roads are poor and the wages are relatively high. Still a large enough market to make it work though.