at what "speed" do you expect your graph to read "depths" ?
do you expect your 2D sonar to pick up bait fish pods at a high rate of speed ?
what do you use the different graph apps to do ?
how do you expect a graph to help you catch more fish ?

I expect the digital depth data overlay to give me a depth reading at any speed. At higher speeds, the graph itself may not have much to show me. I'm usually looking at a map with the digital depth data overlay when in Point A to Point B travel mode, so don't see the graph much. I would not expect it to pick up bait or other subtleties then. Below 10 mph, I want the graph to show structure and cover I can't see from my vantage point - to the hope that I can find fish there. I don't have to see an indication of fish to try a spot, but it is a nice bonus.

depth at any speed. Don't expect it but it does pick up bait fish at high speeds. Helps eliminate areas

I guess it depends what you mean by high speeds. Up to 35-40 I get good readings from my HB and see all kinds of pods. But after that it doesn't read for [censored], just depth