Do you mean a GPS, Chartplotter and FF or MFD? All companies have good units. A Multi Function Device allows you add other components like radar usually from the same company and not other companies. You need a MFD and transducer. That is all I have for now and will upgrade after I retire and move to FL full time. Next is the budget? $1K, 2K, 3K, 4K. It is all about the Ks. Next is screen size, maps (charts) and transducer like CHIRP, Side scan, etc. There has a lot of advances in marine electronics in the last 3 years. You may need a high end transducer built in the hull vs and transom bolt on. It depends on your needs. You may need a radar for fishing and navigation in high congestion areas. Then add sat weather if venture out
Post your boating and fishing needs and others with more experience than me will chime in.
You should have decent full functional VHF with AIS radio and antenna already. I have a PLB , handheld VHF radio with AIS, strobe lights and decent life jackets
I bought my Garmin years ago (545s) from Jim at Boe Marine . I think he is the best like TabMan at Bennett.
Go to a marine store like West Marine and familiarize yourself on how the units work. You may like buttons vs touch screen. Look at the charts (maps) details, screen size, resolution, etc
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