Hi harleynut,
Post #182 here includes the better options in the Rochester and Minneapolis/St Paul area that I know of. My first step woud be talking with Chuck at http://www.myrestassuredmattress.com/ which is right in Rochester and is a manufacturer that I think highly of.
Original mattress factory is a regional factory direct that also makes high quality products with good value. Talatech latex is the trade name for Talalay latex made by Latex International and is a high quality material. They only have two different versions of latex mattresses and both have the same support core and one adds extra foam on each side of the core. They also have one memory foam mattress which they recently came out with that also uses high quality memory foam.
I would also be aware that the specialty mattresses (memory foam and latex) they have on the floor are set up on an active innerspring which will affect the performance and feel of the mattresses compared to the more common foundation choice for these types of mattresses which is a firm non flexing foundation. I mention this because if you test these mattresses on a rigid foundation (such as an adjustable bed) they may be more or less suitable for you than they are on a more active innerspring.
Phoenix