Anyone use the DeLorme InReach SE or Explorer? Thinking about getting the explorer but have some hesitations. Anyone know how good the GPS functionality is for navigation? Doesn't look like you can see topo on the unit itself and have to use a cell phone? I currently have a Garmin GPS I really like, but would like to be able to text my wife when I don't have service. I don't think I want to go with the SE because I would still have to carry my Garmin for navigation.