I prefer my own bed or floor with enough room to curl, stretch and run marathons in. I'm really sensitive to sounds, touch, anything when I'm trying to sleep... so the duvet can't be too soft or too textured and the quilt has to be light. There has to be some sort of outside sound as well; not all the time but just enough to know there's life outside lol. The room has to be pretty dark, too. No hall lights coming through the door or streetlights.
When I go to visit friends, unless I know the friend well enough and their hygiene is to my standards I can't get a decent nights sleep. I can start a boxing match with myself if I'm really uncomfortable as well, so it's just easier to either sleep in a separate bed or somewhere away from theirs. I used to sleep in a University friend's bed with her and I slept well in it, but she had a habit of waking me up with her sleep talking and walking... that bed was good tho...
/High maintenance sleeper