Soft chest strap / Wrist-watch design / Wireless speed sensor

The CS 300 caught our eye because as well as being a traditional wrist-watch heart rate monitor, and thus perfect for cross training, it also comes supplied with a wireless speed sensor. The sensor straps to your forks using zip ties, and this picks up a magnet on your spokes as it passes by. The unit needs calibrating for wheel size (unlike the Garmin, which uses GPS to calibrate the wheel size) but this is an easy job using Polar’s extensive manual and easy-to-navigate interface. We had a bit of trouble getting the speed sensor set up properly: the sensor needs to be towards the top of the forks to be able to communicate with the watch, but obviously, the higher up a suspension fork you go, the further the spokes are from the stanchions. Once set up, the system did exactly what we wanted — it told us our heart rate and one other piece of info, be that speed, time of day or training intensity on a graph. It was easy to read even when wrist-mounted, and with the supplied bike mount, it’s even easier to see.
Polar’s chest strap is regarded as one of the best in the business, being soft material rather than plastic. To be honest, if you notice the chest strap, you’ve probably got it way too tight, but we didn’t notice the Polar strap, so that must mean it’s good.
The Polar watch was the nicest design on test — this is a watch that you can wear casually. If your fitness regime isn’t restricted to mtb’ing, or you want something very intuitive (who doesn’t?), we reckon the CS 300 is a good choice.