Just my two cents---I bought one and hated it. Nothing worked. Speed was off, cadence didnt work, etc. etc. (I had my LBS install it since they were doing maintenance anyway so it wasnt an installation problem). What also annoyed me was that the speed is measured in round numbers (i.e 18 MPH instead of 18.X MPH). Sure its a small point, but it just bugged me since averaging 18 MPH is different than avergaing 18.9 MPH. The head unit was also too bulky for my liking. Also, its not the easiest thing to figure out.

For what its worth, my cousin said he was buying one, I told him not to, he didnt listen...two weeks later it was on ebay.