Originally Posted by brianogilvie

If what you want is mapping, the eTrex series would be worth considering. They're slightly heavier than the 800, which weighs 3.5 oz (98 g), and they're bulkier, but the difference is minimal.

The Edge 800 is a cycle computer and training aid: it gives you a whole series of metrics (speed, average speed, lap speed, lap distance, total distance, total distance climbed, grade, and many, many more), it has a lap button for easily recording laps, it can be programmed with different workouts, and it also has the basic mapping and navigation functions. It's best to think of it as an Edge 500 plus mapping. Some of the other Garmin devices can be used with a heart rate monitor and cadence sensor, and have some of the same metrics (the Oregon series, for instance), so the line between cycle computer and GPS mapping unit is blurry, but there's still a difference in emphasis.