They were very comfortable in many cases. The water container conformed to your body and provided very evenly distributed pressure. Having a heated bed was very

They were very comfortable in many cases. The water container conformed to your body and provided very evenly distributed pressure. Having a heated bed was very nice in the winter. You usually had an extra pad on top to reduce contact with the vinyl container. It was hard to sleep with someone else though as their movements tended to cause you to bounce around. Later versions had baffles that reduced the motion of the ocean. They were very heavy. I had to get rid of mine when the downstairs neighbor could no longer open her door due to warping of the doorframe in a very old house.