I used a 3hp Minn Kota on my 17' Whaler last year. It worked great as far as noise and speed, but the battery life was terrible. I would guess three hours tops. That was with a standard 12V RV battery.

Good luck
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In the legend of King Arthur, the Fisher King was a renowned angler whose errant ways caused him to be struck dumb in the presence of the sacred chalice. I am no great fisherman, and a steelhead is not the covenant of Christ, but with each of these fish I am rendered speechless.