To me a GPS is indispensible, however I do carry paper maps as well. A GPS is great for seeing detail all around you. They are also great to show you the best way to get from Point A to Point B and back again (a couple of button clicks and a route to get me home from anywhere in North America is displayed). The are great for record keeping. I record "Tracks" that will capture a point about every 10 seconds or so. When I get home I can review every point along the route. If I want to go back to a particular point in the future I've got a record of it. Also, as shown in the post above, I can get a profile of my trip that shows all of the altitude changes.
I have two. One is battery powered (Garmin ETrex Legend-C) and is a backup. The other (Garmin Street Pilot 2820) is not and is the one I use most of the time. It also has a built-in MP3 player and I've found that music makes a big difference on longer trips. It also has voice cues and will tell me to "in 3 tenths of a mile turn left on Davidson Drive, then turn right" so when it's navigating I don't have to look at it, only listen. It does speak the road names as well and doesn't just say "Turn Left" or "Turn Right". That is a big plus in crowded city areas because sometimes it's hard to tell exactly what road to turn on.
But .... a GPS won't change the way you ride, it won't do everything for you, nor will it put gas in your tank. They are great to have around, but for route planning I still prefer either software on my computer or a plain old paper map. They are great tools, and I won't go far without one, but they are just another tool. How much you get out of them depends on how well you learn to use them and then put them to use.
Scott Craig - Nashville, TN
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