I have an older Magellen model 410 and have the Mapsend Lake Winnipesaukee map. It does a really nice job, but has no Navaid (buoys) info. I therefore bought the Bizer Waypoint file and installed it. It has a lot of great information. You should be able to also add additional waypoints as needed for the areas you frequent. For me, it was the black tipped spar off the SE end of Treasure island. I keep my boat at West Alton, and returning from Wolfeboro or Alton at night or in the "gloom" can make spotting this spar interesting. Sooooooooo, I just sidled up next to it one day and established my own waypoint for this spar.
A nice feature with the Bizer Waypoint file is the "safe passage" waypoints he put in, such as by Sandy Point - Echo Point - Little Mark in Alton Bay, and off the eastern end of Rattlesnake, I believe the area between Rattlesnake and Diamond has one... Learning these waypoints, coupled with common sense and the chart, navigation is a lot easier. As I have said before...thanks Bizer!.
Also, most GPS units create a visible track, so if you are returning the same way you came, you can follow the "cookie crumbs" you left on your way over/out there. Biggest thing though is the common sense, and don't rely on the GPS alone. Always know where you are at, and know that you can continue if the GPS goes out.
Whatever way you go, fancy or plain...Have fun

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