Any of the mattresses from the companies listed in the “The Underground
(Our Membership)” section are of higher quality (Density). More info from Phoenix on Costco mattresses:https://forum.mattressunderground.com/t/aerus-mattress-natural-plush-natural-ultra-luxe
I bought from Brooklyn Bedding online and while they are in Arizona (I’m in Florida), I still took delivery in under a week. I chose the Aloe Alexis Firm (Level 3)…excellent bed in my opinion and my back pain has diminished.
Good luck with your choice.