Hi computergeniusiamnot,
The closest “list” of better choices to you is in the Des Moines area in post #6 here. One of these is a member here which means they are a recommended choice. They have an outlet in Ames and of course it also helps that they offer a 5% discount on their mattresses for the forum members here 
While they would involve a drive … they do carry a complete range of mattresses including gel memory foam which use good quality materials and have good value. They work directly with a local Restonic licensee and Joe the owner is very knowledgeable and helpful.
If these are too far away for you … then let me know and I’ll take a look at what may be available more locally to you but they would likely require more research to make sure that they have the knowledge and experience to help you make good choices and to also make sure that they are willing and able to tell you the quality of materials that are in their mattresses.
Phoenix