I have to agree with Anton here Fiona. Latex and memory foam are two of the most expensive raw materials in the mattress industry. That is if you are dealing with legitimate latex (Talalay) and memory foam (3lb +). Quality mattresses that use these two materials are bound to be well over $1,000 in a queen. Are the prices of the two models you mentioned around that price range? If your buying from a large chain mattress store, you have to imagine that product costs them around 1/3rd what they're selling it for.

Perhaps take a look at a mattress with a pocketed coil innerspring and a high density, medium-plush foam in the comfort layer. As I mention all the time on this site, check out any local manufacturer's in your area. They will give you the best price and good quality.

Good Luck!

NN-

I think Nick's post is right on for your best value. A lot of bed manufacturer's are making pocketed/encased coil beds nowadays and those are the best for support. If you shop in full/queen size, between 600-800 coils in the mattress should be really good support but not so firm that it will stress already tender pressure points.

*edit - If you use a platform bed, you can reinforce your support with a bunkie board or plywood. If the platform bed has a lot of slats(12 or more) and they are no wider than 3" apart, your mattress should be just fine.

Fiona, sorry to hear you are in such pain.

budget wise, latex and memory foam are about as expensive as it gets in the mattress industry.

as a manufacture, i always advise against putting any mattress on a slatted bed frame. the mattress is not properly supported and may cause the bed to wear out faster. if nothing else, i would suggest putting a large flat piece of wood over the wood slats so your mattress has a flat surface to work with. this will help support your mattress, and keep you from buying a more expensive box spring.

lastly, and this goes against what i said about wood slats.... i would probably suggest a waterbed. the reason is, modern waterbeds offer great backsupport and the ability to adjust the water lever to make the bed softer or firmer by adding a few gallons of water. also, since waterbeds are heated, they help relax tight or sore muscles.

once company you may want to look into is Aqua Dynamics if you are in the EU, or if you are in the USA, Sterling or even American National might be your best bet.

OH, Fiona...that kind of pain is sooo difficult. Being in the UK, you might consider trying a wool topper. There are some wonderful products on the market..I've seen some on Amazon in the UK. Wool seems to help many fibromyalgia sufferers ( my sister-in-law is having a similar experience to yours). Best of luck in your search...I hope you find some relief.