I've been thinking about buying a Lakemaster Map Card to use on local lake. The lake is on the map card. Now I have second guessed myself. Why do I need it? I have a Helix 10 G2N. So I travel the lake with unit on looking for crappie. If I have a map on my unit how does that help me find crappie? All I will be seeing is a contour map of lake. What am 1 not understanding?

