We changed from 1"Memory foam because it started to break up. And it was a nuisance. Whenever I complained about the length of time since the last rumpy pumpy.. It would pipe up with ," You last made love 3 days and 12 hours Ago."... It had to go!
Bought a cheapo mattress topper, from TK. MAX It works a treat.
Light, easy to pack and clean. Alas there is no brand name on the label.