I use a Garmin 546 for my GPS and a Garmin 300C for my depth/FF along with a Garmin GDL40 Weather interface. They are all hooked together using a NMEA 2000 network.
I have the GPS and the depth/FF separate as I didn't want to rely on one unit.
That's my combo.... running a 585 w1k ducer
Garmin has it going on in the chart plotters but furuno is top dog in the sounders....my.02 Posted from my iPhone/Mobile device
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Things done at the last possible minute are done with the greatest possible information. Procrastination is, therefore, the most efficient means of doing things.