When it comes to choosing the firmness rating of your bed its really down to personal preference and what gives you the best nights sleep possible. Different companies sometimes vary in how they present firmness ratings but here at home furnishings UK it couldn't be any easier. All of our beds comes with 6 different firmness ratings and a rating bar!
A "Soft" rated mattress will snuggle around the user giving a nice warm cuddly feel and the "Ultra Firm" rating will give the user a more stable feel and gives better back support if you suffer from back aches/pains.
Here's an example of how the graphic is used HERE or HERE