How to choose the right mattress

I have been doing some research on what kind of mattress I should buy for my new bed. Below are two articles I can wholeheartedly recommend:

Buying a mattress (Choice, Australian Consumers' Association, 10/04) - Comprehensive, balanced, and informative.

Going to the Mattresses - How to cut through the marketing gimmicks of Sealy, Serta, and the rest (Seth Stevenson, Slate, 22/11/00) - Opinionated, provocative, and bloody good read!

If what these articles say are true, these are some of the things you may not know about mattresses:

One of the most confusing things about shopping around for beds is that it's almost impossible to find identical models from store to store, making it difficult to compare prices. Stores want to carry their own 'exclusive' models. (Choice)

Mattress makers rename identical products for each different retail store. Different labels, exact same guts. Why? Obfuscation. It's hard to shop for the lowest price when you can't compare apples to apples. (Slate)

The big-name mattress makers (with some exceptions) all get their coils from a single company for their highest-end mattresses down to their lowest. (Slate)

The comfort layer is what lies between you and the springs — it determines how hard or soft the mattress feels against your body. A manufacturer that makes a large range of mattresses will often use the same spring unit but vary the fillings. (Choice)

Some mattresses use more coils but thinner-gauge wire. Some use thicker wire but fewer coils. And everyone uses radically different configurations that make comparisons meaningless. (Slate)

Beds with names involving 'paedic', 'chiro', 'ortho' and so on aren't necessarily better for you than others without medical-sounding terms — it could just be the marketing. (Choice)

Also be wary of endorsements from medical-sounding organisations. While some are legitimate, in some cases manufacturers buy the rights to use one, rather than earn it, and other manufacturers have been found to claim endorsements from impressive-sounding but non-existent organisations. (Choice)