Hi Paul.

The first thing to get your head around is the ludicrous terminology banded about re Soft, Medium or Firm tensions (SMoF). There is absolutely no universal standard of tension which makes references such as 'regular support', Orthopaedic Support, 'firm support' or whatever quite a nonsense.

Logic dictates that a ten stone slip of a thing will find the comfort and support of a particular mattress completely different to someone with a greater (or lesser) bodyweight than theirs - it is completely subjective and practically impossible to identify a mattress as SMoF without attributing that reference to a particular body weight.

The next thing to bear in mind is that ALL mattresses are built using just two equations - SUPPORT AND COMFORT.

No mattress will be right for you if these two aspects are not equally balanced to the bodyweight applied.

For example, our ten stone lady above does not require excessive support - their bodyweight will barely be getting through the comfort layers to utilise fully any kind of spring system. Conversely, your wife at 17st will be looking for adequate support and adequate comfort - and as the case of your Tempur and Ortho examples above proves, it is quite difficult to get this right when you take into account additional personal needs.

The final factor to complicate further comes down to budget.

You will see that all mattresses that have high-end comfort layers (natural fibres) will also have a choice of spring tensions (gauges) in order for the mattress to be made to suit your individual requirements, but this additional choice usually comes at a price. The vast majority of mattresses out there will be a selection of 'off the peg - find one that fits' option which is where your (and everyone else's) dilemma lies.

For your requirements and your wife's personal needs, I think you should take time out and look at some high-end mattresses such as Vi-Spring [try Furniture Village]. This will give you some indication of how a premium spring unit (Support) should be working with premium comfort layers (Comfort). Once you actually know what is available at the top end of the market you will be able to make the necessary compromises to fit your budget.

Finally Paul. It is our view that if you are quite happy with the feel of your current mattress it would be wise to stick with the same model/manufacturer. I have just noticed that the PSBC website states that their new collection is coming soon. Their new product range will be dramatically reduced from their previous offerings and so your current model may have been discontinued, worth a check though.

Keep in touch and let us know what you find.

John and Ryan.