I am 5'9" with a slightly shorter inseam and am on the medium and like it. I got a great deal on a left over '15. don't be afraid to low ball on your offer 10% should no problem.

I'm 6', 32" inseam. Did a 47-mi ride on a rented Defy 5, size M (their chart says M/L for me). I couldn't have been happier on that size bike. It was fantastic. I can't imagine the M/L being any better.

Currently looking for deals.