Not really similar to computrainer in that it says nothing about your power. Only tracks your speed and cadence. Depending on your trainr, or how tight you screwed it onto your wheel or how much air is in your tire, your power needs will be very different. Perhaps even from one day to the next.

I have had one for about 3 months. It uses the NetAthlon software that Computrainer uses so the user interface is the same. It keeps me entertained while on the trainer & rollers. It does a good job of monitoring/recording heart rate, cadence, speed, time, and distance data. If you're into it you can use the data to track progress over time. Utlimately it's just an extention to the functionality of your rollers or trainer. And frankly, at <$200 for a complete setup it's a no-brainer.