There are two other options - closed cell foam mats and self-inflating mats. The former were, and still are, very uncomfortable but many find that the latter provide the best ground insulation, bed-feel and comfort of all the options. But you have to not mind sleeping almost level with the floor.
Aero bed Raised comfort king on special offer at the mo at tesco.com 49.99 can highly recomend , just remember to insulate below and above as the air can get a bit cold