If you are reading this then you probably have a basic understanding of the benefits of training with power measurement. While not cheap, a power meter can be one of the most effective training tools you can get besides your bike.While everyone talks wattage, a power meter will also give you other useful data like heartrate, speed, cadence and distance. If you use a GPS like the Garmin 705 or 500 as your bike computer you will also have mapping data and elevation.There are two main power meter types: hub based and crank mountSaris PowerTap HubThese are the industry standard for hub power meters. You replace your rear hub with the Power Tap and have computer on the handlebar that displays and records the information. Power Taps are popular because they are easy to swap between bikes and are well priced compared to crank based systems. The drawback is that if you swap your wheels to a race set that doesn't have a Power Tap hub you no longer have power measurement. Because the Power Tap is wireless and used ANT+ data transmission you can use either their computer or any ANT+ compatible computer. The hubs are a little heavier than high end models but by only a few hundred grams so you can still build up a light race bike with a power meter.SRM crank based systemThese are the pioneers of the power meter. Originally only available to pros due to the cost, SRM makes models that while not cheap are at least within the price range of the high end serious cyclist. The nice thing with the crank mounted systems is that you can run any wheels. The system is accurate and can be used to help with pedal stroke as it measure each legs pressure on the pedals. The system comes mounted on a crank.Quarq Cinqo crank based systemThe Quarq is a new option that makes the crank based power meter much better priced. There are a number of cranks that are compatible so you can get a nice upgrade if the crank you have isn't one of them. The system is easy to use and is compatible with ANT+ bike computers. Like the SRM, you can swap your wheels without giving up your power measurement.