Thunder Bolt
Silly old bat
All you are to get is "I've got one of these and it's great" sort of comments. Everyone is different, you should go to a supplier (who hopefully knows what they're talking about) and try out, as best you can as many as possible. John Lewis generally know their stuff
I agree the comments "you get what you pay for"
I don't agree. We bought a Silentnight bed and divan for over £800 20 years ago and had to throw it out within 3 years. That's when we bought our Ikea bed frame and mattress. There is quite a difference in our weights but we've never had dips in the mattress.
As pointed out above, Which found the Ikea mattress better than many more expensive ones.