Plus being Costco, its easy to return if you don't like it.
"Merchandise: We guarantee your satisfaction on every product we sell with a full refund. The following must be returned within 90 days of purchase for a refund: televisions, projectors, computers, cameras, camcorders, touch screen tablets, MP3 players and cellular phones.
How to Return: For an immediate refund (including shipping and handling), simply return your purchase at any one of our Costco warehouses worldwide. If you are unable to return your order at one of our warehouses, please email customer service or call our customer service center at 1-800-955-2292 for assistance. To expedite the processing of your return, please reference your order number.
If you request an item be picked up for return, the item must be packaged and available for pick up in the same manner as it was delivered.
If your order was delivered "curb side", it will need to be available for curb side pick up.
If the item arrived to you in a box, it will need to be in a box at the time of pick up."
The mattress comes compressed in a large box and decompresses fully in just a few hours. There is no way that you will be able to get it back in the box.
I'm assuming that if you want to return it that it will have to be as is.
How long after you purchase it will Costco take it back??