GPS, maps, or both

Before Christmas I ordered all the maps for each National Park we will be visiting, the maps are great and include all the trails. Then I decided should I get GPS, or not. Price was a consideration but after much searching I found the Garmin GPSmap 60 at an eBay store and it does the job for a low price, 24 hour battery life and waterproof. This is great for peace of mind when hiking and will come in extremely handy.