First thing, research Navionics and Lakemaster and Lowrance Insite. Figure out which one gives you the best coverage on the lakes you fish. From there you can start figuring out which unit would be the best to run. In this case say Insite gives you the best coverage then Lowrance is only option. If Navionics gives best coverage then Humminbird might be best option even though some of their chips will run in Lowrance. If Lakemaster is best then Humminbird is only option. Never used Garmin or their Lakevue but if it covers your lakes I have had guys tell me it's pretty good with contour lines. Only Garmin Lakevue is compatible with Garmin.
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Charlie Weaver USN/ENC 1965-1979