just like running shoes..whats good for me wont likely be good for you.
you HAVE to go to the store and lay on it and choose what you like. theres no way around this if you want to do it properly.
go to sleep country and lay on some shit. it doesnt take that much time. nobody here can tell you what will feel nice to you.
I dont like memory foam because they typically get too hot. other than that...not much else to say.
go lay on some mattresses.
Sleep country is nice in that they deliver and take your old bed. you also have 60 days to sleep on it and can exchange at no cost if for some reason it turns out to be terrible.