Looking to purchase a new mattress and need advise please

Hi ,
We are looking to purchase a new mattress and have been in a few stores to see what would be best and I was wondering what you advise? We have come to the conclusion that as my partner is a hot sleeper so memory foam does not work for us. We would also like a mattress that offers good support for our backs so have been looking at a medium firm if there is some kind of gel topper or potentially a medium if it was just a pocket sprung mattress.
I can see that you have some fantastic reviews and was wondering what style mattress with yourselves would be best to look at?