These mattresses are made to old school way from twenty years ago. I remember it well when we went to the annual furniture show in January 2000 and all of the three S's (Simmons, Sealy and Serta) announced that "we have good news for you, your prices are not going up." I was stunned until they told me they were going to make mattresses one sided only going forward. "Don't worry we'll make them better so it will not matter" they said. Well warranty issues piled up and one by one I stopped selling those major brands and I can't imagine a day when they will ever be back on our showroom floor.
We have three very high quality two sided (you can sleep on either the top or the bottom for extended life span) on display in our Mississauga Ontario showroom right now. Having said that every mattress in our store can be made two sided and therefore flippable.