I've got a 797 on a 16 ft tracker with a 45# tm and it works just fine. I was playing with it slow trolling at about .5 to 1 mph, depending on the head wind, and had the chart speed set at 1. Looked really clear and the proportions on the screen looked about right and was clear. I read on here somewhere that the rule of thumb was to set the chart speed to about the speed you were running. Works for me so far. But to answer your question, from my limited experience you are good to go.
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