Hi Mark,
 
Thank you for your question. The advice used to be that anyone with back issues needed a firm mattress but this is not the case. You need the correct level of support for your height and weight with the right spring tension. This will allow your body to find its own level and not be forced into an unnatural position. 
 

 
Spring counts are always given for a kingsize anything between 1000 and 2000 pocket springs will give you the correct support as long as the gauge of wire used to make the springs is correct for your body weight. There are mattresses that have 20,000+ springs but you will find that there are only actually 1000 springs and the rest are micro HD springs that inflate the spring count and fill the space where more luxurious upholstery layers should be.
 
                 
 
The upholstery layers, also known as the comfort layers, should be determined by how you sleep and your comfort preferences. You say you need a supportive mattress to stop you from tossing and turning in bed but if you are a side sleeper and currently sleeping on a firm mattress, it could be your mattress that is making you move around a lot in the night and preventing you from having a good night's sleep. We do not recommend firm upholstery layers for side sleepers as this can cause pressure pains in the shoulders and hips. Likewise, for front and back sleepers, we do not recommend soft upholstery as this can cause those to sink in too much which can cause lower back pain.
 
   
 
Natural fibres will provide the coolest sleep surface and help you to regulate your body temperature. Wool for instance wickes away heat and moisture quicker than any other fibre so it keeps you cool in summer but warm in winter. Memory foam is the warmest type of mattress as it requires body heat as well as pressure to be able to mould to you. It retains this heat and feeds it back to the sleeper making them overheat. If you prefer a foam mattress, 100% natural Latex would be the coolest material for this type of mattress.
 
If you would like any further information or to discuss your individual needs, please do not hesitate to give our small friendly team a call on 0161 437 4419 and they will be happy to advise you further as to which model would be the most suitable.
 
Kind Regards
Michaela