Hi T2P,
As you probably know memory foam and latex are very different materials with very different properties. There is more about the differences between them in post #2 here but it’s good to hear that you want to try some latex mattresses in person because the best way to know which type of materials or which type of mattresses you tend to prefer will be based on your own personal experience.
The better options or possibilities I’m aware of in and around the Minneapolis/St Paul area (subject to making sure that any mattress you are considering meets the quality/value guidelines here) are listed in post #2 here.
If you are interested in testing a range of different latex layering combinations and firmness levels then a visit to Deborah at DIY Natural Bedding
would probably be well worth your time.
Phoenix