Great for Small Boat Use and Geocaching
I got my Garmin 78sc a couple of weeks ago, to use not only on the water (Chesapeake Bay), but for hiking and geocaching. By now I've sailed for 3.5 days,(about 18 hours total run-time), before needing to change the alkaline batteries, so I'm fairly satisfied with the battery life.
Lots of marine features and alarms, such as anchor drag alarm, low water depth alarm, (from map depths) Man Overboard function, etc; The coastal marine plots seem fairly good and accurate to the paper chart I have of Upper Chesapeake Bay
Price kinda high, but the accurate marine charts are worth it; Base maps (on land only--the marine charts are good) are a joke, and optional 100K topo map software are still sparsely populated