I'm retired and I considerable older than most guys on this net and the computer age passed me by so I live by the Keep It Simple Stupid system (KISS) which works for me.I fill all boats up once it bobs below the half way mark as you never know what you are going to run into seas wise or for how long. The thought of running out of fuel has always given me the pucker syndrome ..When I hear it gurgle out the air vent I know I am good to go. I still use charts even though I have a GPS just in case along with two VHF's on each boat. We have a lot of million dollar plus sport fishies down here maxed out with electronic bells and whistles, space age thrusters, electric grouper reels , crystal clear eisenglass enclosures etc and they still hit oyster bars, shoals, miss buoys and GPS markers, go way off course,run out of fuel etc. Some of these young captains look very sporty in their matching crew Greg Norman yacht wear but I would doubt that they could run an ocean compass course which most little sea scouts can do their first summer..To make a long story short I would say buy one and have someone wire it up so it dont interfere with any of your other electronics but still maintain your tanks as full as possible..Frank