The Quarq Power Meter is a crank-based power meter as opposed to the Saris/Cycleops Power Tap which is wheel/hub-based. So, if you have your favorite set of wheels you can keep them. Or, if you have a Time Trial bike and you like to frequently change wheels, i.e. disc vs. deep dish, you can choose the Quarq PM. You can't do that with the Power Tap since the Power Meter is built into the hub/wheel.
I don't know much about the reliability of the Quarq, as compared to the Power Tap, but I've heard the accuracy is just as good- if not better. (Could be the reason why their Power Meters are currentlly on back order.) The MSRP of the Quarq is $1800 (which is more than the Power Tap $1300) and does NOT include a Computer Head Unit. But, if you're the lucky owner of either a Garmin Edge, Saris Joule or other Ant+ Sport (Wireless) Computer Head Unit you can use that. The only negative, as of now, with the Quarq is that there is no calibration software/program/computer..so, if it becomes out of Cal you'll have to send it back to Quarq. I heard they are working on an iPhone App for Calibration in the near future? iPhone? What's with that?
The only other crank-based Power Meter on the market is the SRM Power Meter which MSRPs for about $3500. Ouch! Although I've heard the SRM is the "Cadillac/Escalade" of Power Meters. Not only is it the most reliable it's the most accurate on the market. (Gotta love that German Engineering.) Could be the reason why all the Top Pro teams have them (SRMs) on their bikes. I can become an authorized SRM Power Meter Coach/Dealer but why? Who can afford it except these Pro Teams with million dollar sponsors. Hell, SRM probably gives them to the Pro Teams for FREE...just for advertising.
I'm still waiting for the Garmin/Metri-gear pedal based Power Meter to hit the market..but then again, I've been saying that for 2 yrs. now.
I'm ready to put my Quarq Cinco PM order in. If any of the athletes I coach, or coached in the past, want one at a discount..email me and I'll show you the prices and options. I'll be ordering the end of this week..so don't wait. Also, there is a 4 week back-order as of now which is why Quarq is only taking deposits right now. I think they want a $600 deposit up front.
Power ON! Coach Rob