I looked into this GPS unit and it seemed like a great added safety device for non- emergency situations or just letting friends and family know things are OK when out on the big pond. I tried it and it is very accurate. It can show your location and track your path on a google map from a computer at home while you out there. It will also summon a tow service or the USCG at the push of a button via direct link. Wterproof and portable, it doesn't rely on the boat's system for power or antenna.
Just some added safety. I still have two GPS EPIRBs on board as well. One mounted in a rack in the open and one in my Ditch bag. All in all, cheap safety. Before that next rod & reel purchase.......think about some safety first.