http://www.lookcycle.com/en/us/route...keo-power.html
The LOOK Keo Power pedals are only spec'd to work for 170, 172.5, 175 or 177.5 mm cranks. So, trackies who like 165 or 167.5mm are out of luck. Not sure why crank length matters, though, since the strain gauges measure torque. Torque is torque, right?
Also, the fact that it's not ANT+ is just plain stupid. They want force people to buy their sub-standard Polar head units.
Here's a field test of 3 power meter systems on the same bike (wheel, cranks, and pedals):
http://www.bikeradar.com/blog/articl...-pedals-32678/