I use my heart rate monitor all the time, when biking or spinning. I think it is a great tool for training as well as getting the most speed out of this old bod. Mine's a Polar CS100 with all the bike computer features plus the standard pulse stuff as well. I've had it for 4 years now and wouldn't consider riding without it. How many out there are using a heart rate monitor on their rig? And if so what unit?