I just replaced my oem mattress. I got mine from mattress insider. I am very happy with it. I can access my storage under the bed no problem the struts hold it open. It is a great RV mattress. I got a custom made memory foam king 75 X 80 x 8. They have a money back guaranty. If you don't like it they will give you 100% refund. All you have to do is donate the mattress to a charity and send them the donation ticket and they will send you your refund but not for custom made sizes. This is the mattress I got in a custom made size.
http://www.mattressinsider.com/luxur...mory-foam.html