Hi mattc58,
SleepEz is certainly a great choice and as you probably know is one of the recommended members of this site. Post #21 here includes the others which specialize in online or “on the phone” sales and service.
While many of them are quite different in terms of their mattresses and the options they offer … they are all among the best in the country IMO in terms of their quality, value, service, and the knowledge and guidance they offer to their customers.
Phoenix