previous mattress as ikea and it had had it springs gone. so any mattress would be better and comfier. also never had a £400+ mattress so my opinion is in this budget range sub 200 and the rating is for this price range.
 sides are not well supported but i havent fallen out of bed
 memory foam is a decent amount and density by all accounts
for the money i am not complaining and it is a million times better than our old mattress.
arrived quickly, in a box in a vacuum pack, little smell but soon dissipated