I don’t know about Garmin but not all Helix’s are created equal. When I bought my first Helix the 7 had fewer screens and options than the 9. It didn’t make sense to me that same model name had different features simply of screen size. I found this out while playing with demo units at Sportsman’s Warehouse. If you can, go touch a few before buying.
Really enjoy my 73sv, operate some helixs fairly regularly as well. I’d choose the Garmin. Orientating screens, ease of use, screen just seems more detailed IMO.
just for the sheer fact you can add panoptix to the garmin is reason enough. I think lakemaster is superior mapping to navionics but navionics is getting better at least for the mississippi.