I'm thinking about purchasing some high wow factor cranks and I'm not sure about the length. I have been on 172.5. I am 6 ft. tall, and ride a 57cm. Am I costing myself lots of power? Should I be on 175s? I don't ride but a few crits each year and I'm not prone to pedal strike anyway. I need some help on the hills. My 'Cross bike has 175s and they seem easier to turn, but a little slower perhaps. What do you ride? What is your height?