Large
I'm 6'1" w/ a natural inseam of 32 (kinda short for my height). Large would be the way to go for you I think. I rode a medium and managed OK on it in the parking lot but quickly realized that climbing and tech sections would best be handled by the Large frame size.
Do a search for RFX sizing using the "Search" tab---you'll find that your question has been asked several times over. The responses you'll find may help to steer you...