You might want to look at this link: http://www.nettally.com/palmk/crankset.html. This is one of the areas of great debate. There is another thread right now with a guy wanting to go shorter with crank length. I tend to think as long as you can keep your cadence up with the longer crank go for it as the leverage will help on the steep grades. Remember that I also think you need to have your cadence high as well, and the the long length can hurt you here.