Hi merz28,
As MrM1 mentioned they have different designs, different covers, and different types and blends of latex or other materials and different options available both before and after a purchase. There is also more about some of the many factors that can affect the price of a mattress in post #14 here.
There is also more about the most important parts of the “value” of a mattress purchase in post #13 here that can help you make more meaningful comparisons.
You are looking at some great options and none of them have any weak links or low quality materials in their design but you have a considerable amount of narrowing down to do and one of the most important parts of this process will be more detailed conversations on the phone with each of the options you are considering.
Phoenix