I have that exact garmin, yet to get it on the ice though.
Both have "auto chart" to make maps in the summer and then use ice fishing. Hummingbird requires you to buy their special $100 mapping chip after filling up the internal memory, it can hold a handful of hours though. Garmin allows any Micro sd card. I feel Hummingbird has slightly better depth shading options.
Hummingbird works with lakemaster chips, don't even bother with the base maps. Garmin has alright base maps in certain areas. I feel they suck in MN? Garmin is compatible with navionic chip and ...?
Garmin is a touch screen and very easy to customize different layouts. Hummingbird has pre made layouts.
When comparing same size screens, Garmin units have a significantly smaller body vs Hummingbird.
Livescope vs mega live.
Very happy with the price I paid for my 73sv uhd. Time will tell if I stick with it or switch. Bought a boat that came with Hummingbird so I get to trial both which is nice.