They are very cool. I have the older Ciclosport CM414 and this year acquired a HAC4 to add HRM and download capability. I have also tested the Specialized Speed Zone Pro. The Speed Zone Pro has a shorter sampling rate (~5 sec?) vs the CM414 and HAC4's 20 seconds which allowed it to track feet gained/lost more accurately as well as displaying percent grade changes more quickly, but wasn't as easy to navigate as the CM414. There were some other qwerks about it as well, but it's certainly a nice product. I deduced that they were made by same company when the Specialized arrived and had a transmitter that was not only identical to the Ciclosport, but also transmitted on the same frequency. Thus, when I did my side-by-side comparison of the CM414 and the Speed Zone they were both being pulsed by the same transmitter. This is also why you see the HAC4 and CM414 side-by-side in the photo below; both computers run off a single transmitter so I figured what the heck. It allows me to look at four bits of data all the time without having to cycle throught the functions.