Panda LondonPanda Memory Foam Bamboo Mattress Topper

Panda's topper adds a 5cm layer of memory foam infused with cooling gel capsules (what Panda calls HydroFoam), which Panda markets for "cooler, comfier sleep", to cushion hips and shoulders. It earns our top spot because it balances its foam-and-gel construction with a mid-range price (around £160 for a king, from £99.95 for smaller sizes, indicative) and backs it with a 30-night trial and a 10-year guarantee when bought direct. The removable bamboo cover is machine washable and elastic corner straps plus an anti-slip base keep it in place. Versus the pricier Simba below you give up spring-based support and a little breathability, but you save well over £200 and gain the same length of guarantee at a fraction of the price.