Hi CJ - i love my Raymarine in my fc390 I have just about sold. I will be ordering another for my new fc430 console.
I buy this unit for the price sure but believe it has the best sonar in this price range - at times in the lake earlier this year the base model was picking up sinker and 3 trout flies together with trout about to strike - fantastic stuff just like a video game.
In the salt could distinguish sonar targets and after a wee bit of practice could say what was kahawaii, mackeral, snapper, kings..
Charting to be honest not that important to me - I use the unit to find fish and so long as the gps can trail acurately, waypoint and have the major features charted that will do me. In fact I chose the lighthouse chart option - pretty simple charts really - same level as detail as approached to Akld navigational paper chart. Fine by me.