MAXUM -- we have the 53CV, which I think is essentially the same thing in a different package.
The "Stock" Chart is at best "okay" a lot of missing spars-- it will get you around the Lake in a pinch-- but we didn't like the lack of detail so opted to get the detailed LakeVu ULTRA SD card ( from Watermark Marine) as we are frequent night boaters.
After the upgrade -- AWESOME !!
It does take some time getting use to the functions/ controls … it was not as simple and intuitive as previous Garmin's we have had.
Very first tip is to dig deep into the menu settings and find (god knows how I tripped on it) the setting to ENLARGE the map view print/font to maximum -- this will allow reading the actual FL numbers and surprisingly all Black-Red Tops are associated with a number as well.
https://buy.garmin.com/en-US/US/p/576160
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