One of the most crucial advantage missing from buying a mattress on line is not being able to lay on it. This is the first time I bought two mattresses on line. I just could not figure out if I would like medium or firm. What I like is firm support yet with softness and not feeling like sinking into mattress. First I thought medium , but after I read almost all reviews about this issue, I decided to go with a firm one. It was the right decision for me.
One thing is if you have a bed frame with platform,depending on the type of bed, I do not think it is necessary to get a box spring. My measurement shows it is almost 15 inch from the ground. So make sure your sheet supports at least 16 inches thick.