The better power number for a longer effort is Normalized Power to reduce the impact of coasting -
http://home.trainingpeaks.com/articl...ess-score.aspx
Do you have Cycling Peaks software? This is a must as far as I am concerned.
Do you have the Coggan book? This also is a must.
http://www.amazon.com/Training-Racin.../dp/1931382794