i was wondering the same thing. i have powercranks with a powertap and it works fine. but ergomo measures power from one leg. and since PCs force each legs to pedal for themselves, you could pedal one leg and get a power reading while pedlling the other leg and get a fraction of the power of the first leg. i dont know how much or anything, but it makes sense. in the next few years, i am needing a powermeter where i can use PCs or stiffy cranks, any wheel, and the BB will have the hollow-style BB (ceramics). cyclingpeaks is a must too. a new powermeter is coming out called [font=Times New Roman]Quarq. if that can be mounted to PCs by fall of 2010, i would be extremely happy. using garmin 706, etc. wow! perfect![/font]