I effing hate our Tempur memory foam mattress and would never recommend them to anyone. Cost a small bloody fortune, the company doesn't have a return policy (welcome to Turkey) so certainly don't buy online if you insist on going down this route.
Clearly I am like the princess and pea because only I alone could tell that that there are huge blooming crevices and pot holes on the mattress that retain the memory of a previous sleep nights indefinitely so you feel that every nights sleep is like a balancing act and a slight move in the wrong direction will send you toppling over the edge into oblivion.
Seriously a bog standard mattress at a fraction of the price will serve you very well and if it doesn't it won't have cost you the earth if you feel the need to buy a replacement.