MontBell makes some of the best bags on the planet hands down! Their down bags are some of the lightest and smallest packing you can get for the temp rating. Their sizing is dead nuts though. I am 5'10" 190lb and I bought a regular first. I did fit in it but I was hitting both ends. I went with the long and love it. I like a couple extra inch's of room and I can stuff some cloths or a water bottle in there if I need them warm for the next morning.