Hi tennisbanker,
You are certainly looking at some good options 
You’ve probably read this already but I would make sure you’ve read the mattress shopping tutorial here.
When you are considering an online purchase that you can’t test in person then the most important part of the process would be a more detailed conversation on the phone with each retailer/manufacturer you are considering (see mattress firmness/comfort levels in post #2 here).
There is more about the different ways that one mattress can “match” another one in post #9 here that you can use as a reference point in your conversations.
Once you are down to final choices between “good and good” and there is no clear winner between them then post #2 here may be helpful in terms of “how” to choose between them although at this point it would really come down to “informed best judgement” since there aren’t any “bad choices” between your finalists.
You just have to let them know you are a member here or use their promo code
Phoenix