I'm 5'9" tall and used to shoot a 30" draw length. I shot this length for years until I went to a bow shop run by a gentleman who shot competively with several state and national titles. This man told me that 30" was entirely too long and told me that you should not lock your left elbow (if a right handed shooter) but keep it slightly "unlocked". He set my bow up for a 28" draw and I never looked back. My accuracy went way up. I did loose a bit of draw weight, about 7 LB, but I'll take the accuracy anyday.
Oh, and to that guy who gave me the advice - thanks Chuck.