The Polar CS300 heart rate monitor is a mid level HRM that packs quite a lot of features for a more advanced athlete looking to really analyse and improve workout sessions. It is specifically designed for cycling and cross training and comes with the bike mount and speed sensor in the box, all for $140. Overall this is a great value package.
The CS300 also includes the ability to use a wireless speed sensor that gives you feedback about your pace while cycling. This is particularly handy to have for your training data tracking as you will not be tracking data from your HRM and your bike’s odometer separately. More flexibility in data tracking will give you a much better picture of you perform on each training sessions.