Has anybody ever used or heard of whether this unit is worth taking on the water? For Christmas I recently received this unit for hunting purposes but I have been told that the marine features are actually really nice.. I purchased the TOPO 2008 Maps online and have put everything on MAPSOURCE but was wanting to know if there is anything else that I should have to improve its capabilities? Any help or input of just the features or dos/donts of this unit would be greatly appreciated. I am a college student that fishes as a non boater and would like to start marking waypoints and routes on some of the lakes that we fish at with UofL.