What do you all prefer? I use a kip matt in my tent, will be using it with a tarp soon hopefully, should I bother looking for a hammock, are they worth the extra bother. do they offer a better nights sleep? do they keep you warmer? do they take up as much space as a matt? seen pics but not seen them in the flesh so don't know the sizes, folded or set up. do they make one that will cope with my bulk, im about 18 stone. so presumably will need a double