I have the gelert expedition in long and three quater sizes,can't recommend them highly enough.They are thick and lightweight also very warm when used in a hammock,I don't know about on the ground though as I gave that up a long time ago.
In an Everest programme the other night, I noticed one of the leaders had a 'Ridgerest' strapped to his pack. I use one and reckon they're pretty good, but am suprised that they would be considred OK for Everest.
Jim
thanks for all the advice! I've ordered a gelert one as people that have them seem really positive about them. worth a try, if not ill go back to a normal roll mat and customise i think.
thanks again