Hi SeattleJen,
The first place I would start to help you get past the confusion is post #1 here which includes the basic information, steps, and guidelines that will help you make the best possible choices.
The post also includes a link to some of the better online choices for latex mattresses that are among the best of the best in the country.
With your heavier weights … latex would make a particularly good choice because of its durability but I would make sure that you spend some time talking with some of the manufacturers listed there to make sure that you choose the most suitable mattress for your weights and sleeping style because you will need firmer support and comfort layers than the norm.
You can read more about the differences between a latex / polyfoam hybrid and an all latex mattress in post #2 here. With your higher weights you will tend to “go through” the top layer of a mattress so the Aloe Alexis with a middle latex layer would be a better and more durable choice than a latex hybrid with only a single layer of latex and an all latex mattress in the range of 9" to 12" (some of the benefits of a thicker latex mattress for higher weights are here) would probably be a better choice yet if it was comfortably in your budget…
I’m assuming from your username that you are in the Seattle area and some of the better options I’m aware of in the Seattlearea are listed in post #2 here.
Phoenix