I would put some research into the ducer. nothing wrong with what comes in the box but AirMar has a bunch of surprises for people that do research. I use a Furuno FCV 585 but the unit itself is only half the system I love to look at.

I also separated fish and chart. I had a garmin chartplotter/fishfinder for 12 years and it just recently failed electronically. It was a combo fish/chart unit and I had it wired to a switcher that allowed me to share the ducer for both the funruno or garmin sounders, in case something happened to the Furuno on a trip. The Furuno is so solid that I replaced the garmin with a chartplotter only unit.

2 cents.