I remember a thread about this several years ago with Purple being one of the most recommended brands. My wife really likes a sleep number we slept on in an Airbnb several years ago. Anyone have one? Have you had issues with it long-term? Doing research, I've seen Saatva as one of the new names/highest rated. Would like to get some suggestions/impressions about mattresses, in general. I'm a little concerned about the customer service issues I've read about with the Sleep Numbers. Thanks!