Aldi have, today ( Thursday 3rd September) Slumberdown memory foam toppers in single, double and king size. They are in removable white zipped covers and said to be 3 cm thick. The single size is £29.99 and the double is £34.00. This is just over half the price of the identical item in Argos. They get very good reviews on the Argos website. Mine is just re-inflating so the jury is out here but the cover looks good quality and being able to remove it is a good thing.