Here's my only real contribution, and this is really based on your asking about calories in your other thread. You'll have much more accurate calorie approximations from a HRM that gives you the R-R interval and can approximate your VO2Max. That requires a chest strap - wrist sensors are optical and can't sense the electrical pulses from your heart.


If you get a bike computer, I'd highly recommend one of the older Garmins, like the 800 or 805. NOS computers can be had fairly cheap as everyone wants to upgrade to the latest and buggiest.