I have one right now, (I bought the mid level one) and I don't like it. Not comfortable on the long run and it seems it is actually smaller (by one inch in both

I have one right now, (I bought the mid level one) and I don't like it. Not comfortable on the long run and it seems it is actually smaller (by one inch in both sides and length) than my older mattress. If you are tall it can be a problem. Good marketing, not so great of a product.