Here's a pic of me on my bike (excuse the mess!) - I dont have a whole lot of room on mine either but it works for me - steeper climbs I cant stand up or I just bash the bars and seated on tight turns uphill I occasionally knock the bar - I'd get the medium next time but it works ok - I think I have less space than you to move (shorter stem), dont suffer from pain in my hands but I also dont ride on road on a mountain bike because thats silly.