Holstc, I can’t give you any experience with the Pool 4 map other then that stretch of river is always changing and unless you’re talking about the scour hole it would need to be updated every year.
I have the Navionics map and that gives me a general idea but no way would I trust in for moving fast in some areas.
I don’t know what Doc’s chips are running but as long as it has the side channels, wing and closing dams on it, and use it as a reference you’ll be good.
I had Doc’s stretch of the St Croix color mapped and it was very good for a river.
Doc is a great guy and knows how to take care of his customers.