Go with two Humminbird 998c HD SI combos and be done. It is compatible with i-Pilot Link if you so choose to go that route later. Ethernet cable will allow for you to share data ect.... Keep in mind that you can only save information on one unit not both. That goes for any combination you go with. (i.e) in having two units one will be the main unit to share info to the other.

I will shoot you a PM on different models and pricing....

David @ shut-up-and-fish
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