I am setting up my first i/o salmon boat and am looking for advise on graphs. I was running a hds7 touch screen but not a fan of the GPS love the sonar but the GPS was to slow and glitchy. I am leaning towards hummingbird was wondering how the radar compares to the rest, and is down imaging or side imaging a thing for salmon trolling. I didn't seem to see much on the hds side scan using it last season. the graph I'm looking at is the helix 10 gn3 down imaging Is there a better option I fish Lake Michigan out of Kewanee.