i ordered medium pants and jacket and I'm 5'6. If you search through the 09/10 saga shipping thread, around page 16-18. Theres a picture of a guy named Brenner with M/M pants and jacket. From what I've seen, M should be good for you. People that are around 5'8-6' say L is either perfect for them or too big.
but it come down to how baggy you want your stuff,