If you go to Navionics.com click on the web app, here you can actually see the mapping offered by Navionics vs guessing what it looks like. If you fish the upper midwest Hotmaps Platinum with SonarChart if you venture outside he midwest get the Navionics+ it covers all of US and Canada on one card with Nautical Chart or the same data that came on Premium you download the High Def SoanrChart data for the area or areas you fish.
When you go to the WebApp click on the icon on the lower left corner to view the high def SonarChart layer.
Navionics also offers a year of unlimited updates with the card purchase so your card never goes out of date fro the first year, this allows you to refresh your card with the most current data as Navionics does mapping updates. You can resubscribe fro another year at 50% off of initial purchase price.
Missouri river is 100% better on Navioncs vs Lowrance Insight.
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