There's another forum here for this. "Upgrades" to the basics are cadence, heart rate, gps. Keep in mind you need a wire for cadence and can just get a wrist monitor for heart rate. Also button and character size matter and how many things you can have on the screen at once. For the price have to say the Cateye Strada Cadence is hard to beat if you want cadence and Cateye Micro for wireless without the cadence wire. The Cateye Enduro is supposed to be a good basic one too but I don't know that one.