Per Woodenville's post: simplicity, price, and realibilty. I have a Magellan 310 which I paid $80 new for (on the net). No malfunctioning problems. Granted, it has nothing fancy and only saves waypoint names with four characters, but it does the job as outlined. That said, next time I upgrade I will get something that can have more characters in the save waypoint names. Plus, with the price so cheap you can buy two in case one malfunctions - wouldn't that be a drag in the middle of the Straights or Puget Sound on a foggy day?