Do a search of the Road Cycling section. I was also thinking about getting ROX this past summer but I did a search there and found that a lot of people reported having hardware problems. The non-ROX Sigmas have excellent reputations and I ended up getting a basic wired one that works flawlessly just like all of the previous Sigmas I've owned over the years.
BTW - if you want to go fancy, the consensus seems to be to go with Garmin. Once again do some searches over in the Road Cycling section, and you don't need to get one of the very expensive mapping models - they have less expensive models that allow you to upload the tracking data to your computer when you get home.