I've had one of those orthopedic type mattresses for the last few years and a few weeks into having it I got a 2 inch memory foam 'topper'. First night with it was fantastic! i didnt wake up till much later it was so comfortable!
About 4 weeks ago, I swapped it all out for a full memory foam mattress - and I'm very happy indeed! I got the version which has dense foam at the bottom and a 3 inch layer of memory foam on top - it's quite a bit lighter in weight as well compared to the standard mattress I had before. Bought on Sale from around £599 to £375 from one of the retail park type furniture places.
I've noticed a 'little' acheyness when I wake up but nothing bad, plus I also got myself one of those memory effect pillows - and thats been fine as well !!
All in all - I'm not getting a standard mattress again - for me these memory foam mattresses are the way to go !
The Topper I got in Costco - not sure if they still do them from time to time, i seem to recall paying £120 +VAT for it.
Memory pillow - bought about 4 weeks ago - Argos, its the Super Luxury memory effect pillow, around £25..
I think I saw the 2inch memory toppers from discounters on ebay - take a look there!
DtM! West London & Slough UK!