GPS

The bag of goodies from the MS 150 included a 20% off coupon from Spoke-n-Sport for any "bike accessory". The coupon in my bag was used on the purchase of a Garmin Edge 705 with heart rate and cadence units. Garmin has always had a wonderful product line and to that you can add the Edge 705.
Its a total no brainer to setup. The on-bike info includes at least 3 screens of onscreen data, from mapping to elevation graphs to raw cadence, HR, speed, distance, etc.. After a ride, you can connect it to your computer and upload the data to Garmin/Motion Based. This allows you to see your route and the data recorded by the unit, overlayed on anything from a street map, topo map, google map or even replay your ride via 3D Google Earth. The uploaded files are saved and reviewable from any computer allowing you to see your rides in-depth. For instance. according to the 705, the hill heading up toward the bridge and the switchbacks north of Falls Park on the bike path, consists mostly of 5-6% grades but has a small, short (a few yards) section near the top which the 705 records right at a 7% grade. How the TdF riders can do 10% grades for endless miles and hours is now more amazing to me. You can use the data from the unit to see exactly what your HR, cadence, speed, heading, elevation, grade, split time, etc. is at any given point. If you are thinking of incorporating GPS into your biking, you cannot go wrong with this product.