walmart spa sensations 6" memory foam mattress

The light weight foam will not last. I didn't look at that mattress, but we have just a memory foam topper that we paid $175.00 for about 10 years ago at Sam's Club Queen size and it took 2 of us to lift it out of the package to unfold it and allow it to breathe/accumulate air. It was well worth the money. We just moved the topper into the RV on top of the mattress that came with it and it is very comfortable. Ours is a 3" topper with a removable,washable cover.