I have an old Merlin 3 which is ok for warmer summer nights, but most of the time I use something warmer as I camp in Scotland as we don't get so many warmer nights. The Merlin3 packs to about the same size as my newer Rab Neutrino 400, which is ok to just a few degrees below zero, but I occasionally use both, with the merlin inside the Neutrino for added warmth. This way I don't have to choose between something too warm and something too cold.