After putting up with a terrible mattress (springs poking up all over the place, lumpy, moves every time someone turns over) for months on end, we decided enough was enough! We didn't want a new mattress, because a) we couldn't afford it and b) we'll only be using the bed for another 6 months, so we decided to get a mattres topper. Based on the reviews seen on Amazon, we purchased this 3-inch memory foam topper, and we definitely made the right choice.
It was delivered tightly rolled up in a box (left outside our door for us to find when we got back from work, despite bad weather, which was a bit dodgy, although luckily he'd hidden it behind the flowers (!)), and so when you open it and roll it out it looks squashed, flat and ridged in all the wrong places. It was also smaller than our double bed. We were worried we'd wasted our money, but of course we flattened it out and left it to expand to it's normal shape. Come bedtime, it was perfect. There's a strange, almost chemically, smell about it, but hopefully that will go with time. However, the extra comfort we've gained after just one night's use is enough to make me add my first Amazon review! We were persuaded to buy it because of the reviews on this page, so I hope this will also encourage you to go for it!