@athenian
I bought 3 full mattresses a couple of years ago. Serta, Sealy, Simmons, etc. were all sold to hedge-funds and investor-types. That's the reason why they're not made well and are uncomfortable. They put lots of foam on top, which eventually sinks in the center - and people fall in the center or on the sides.
Don't fall for those long warranties --- these companies never honor them. When dealing with mattress stores, they tell u to contact the manufacturers - who gives u the run-around.
I bought Englander mattresses (3 for my spare rooms) with little foam - $400 each.
You can google mattresses - Serta mattresses and other brands. and read thousands of complaints.
My suggestion is to order from Costco.com (they will take it back after 30 days) or go to ur local Mattress Store (google the store's name on-line and Yelp to read reviews). Have the owner or manager help u - not a salesperson who won't be around in 6 months. They'll explain the differences in mattresses, price, etc. once u tell them what ur interested in buying. You can then lay down on the mattress. That's what I did. I called ahead and got the manager's name and made an appt to go to the store. Things worked out perfectly. I also got free delivery, no tax, free bed-frames, and they took my 3 older mattresses away.
You can also google Royal Pedic Mattresses and read the reviews.
I did my homework and I'm happy with my purchase.
In the past, I had an average priced Sealy Queen Mattress for 29 years -- it was perfect and comfortable.
When I moved to my new home 15 yrs ago, I decided to get another brand new mattress, which is Simmons. Still perfect.
I don't think they're made as well now.