I'd want a large, the harder the spring pushing back the better I'd have thought. Especially with a pump that costs the same as a small terraced house in Liverpool....
They're great pumps, and the 'ask no questions' warranty makes great mental gymnastics maths possible ;) however they won't warranty it if you lose it so:
1.Big size is better for you as will be jammed in the frame
2.Matt can't have one as he loses everything
I'd want a large, the harder the spring pushing back the better I'd have thought. Especially with a pump that costs the same as a small terraced house in Liverpool....