Hi Maggie,
 
Thank you for your enquiry. From looking at a few Somnus Legend models it would appear that the regular spring tension does equate to a medium spring tension. Our medium spring tension supports body weights between 8 st and 16 stone. Our firm spring tension is for individuals whose body weight is over 16 stone. 
 

The model you tried in the showroom would have been softer in the upholstery layers than the one you received even if you had opted for the regular spring tension. This is because mattresses in showrooms have already been softened down by the many potential customers who have already tried it. It will take time for these upholstery layers to soften, it can also take 4 to 6 weeks for your body to readjust to a new mattress. If you have put this mattress onto a platform base it would also feel firmer as it is designed for and would have been displayed on a pocket sprung base.
 
I hope this is helpful and if you would like any further information please do not hesitate to contact the office on 0161 437 4419.
 
Kind Regards
Michaela