I moved my Garman 305 from my road bike to my new commuter, because I like the fact that you can charge it and it gives distance, speed, HR, and cadence...or at least it did. I found that the single sensor for speed and cadence really doesnt work for my new bike...there is too big of a gap between the sensor and magnet on the pedals. Like many others, I find that my natural tendency is to pedal slower but in too high of a gear...so I really want to retrain myself. Any suggestions for a unit with cadence, speed, and heart rate?