Hi imelda_the_chicken,
Post #2 here may be helpful (it’s one of the links in the tutorial post here).
When you aren’t able to test a mattress in person the best way to choose would be based on a more detailed conversation with the manufacturer on the phone. They would be a much more reliable source of guidance than any other forum member (including me) because they know more about their mattresses and the options which have the highest odds of “matching” your needs and preferences based on “averages” than anyone else. There are so many individual differences in needs and preferences between people that I would never use someone else’s experience to choose a mattress.
As flybear mentioned … a mattress with split layers (different on each side) may be well worth considering when the needs and preferences or body types of a couple are very different (see the first part of post #2 here).
Phoenix