School of fish going 3.5 with the console unit. Note how they stratify away from the boat in shallow water. Also note how many fish are in the water column.
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Image from the trolling motor… What side of the boat are you going to fish out of?
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Is it perfect, is it even close? Nope. Does it tell you valuable information? absolutely.. Personally, I think its a beautiful shot. 
As a jig and plug pitcher primarily, this tool is well worth the effort.
If you are a live bait troller, or a plug troller or even a verticle jigger where most of your action occurs behind or beside the boat, this will probably have little value to you. If you are a pitcher, Id look into it.
Fish can be seen at speed higher than optimum (3.5) also. Heres a shot at 10.1.
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You cannot see fish at 39
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