I've been using the FR60 for about 6 months and I am very happy with it. I use it for all track work and for races...places where real-time pace is important to me. I previously used various Polar devises, but got tired of waiting for Mac compatible software. I have found that the Garmin foot-pod is easier to calibrate and it is about 1/2 the size of the Polar equivalent. I think that the Polar units have better heart rate accuracy, but the Garmin is close enough, the pace is more important to me. I run about 30 miles per week including 2 track days, and FR60 works for me.