Just helped a buddy put a garmin on his boat. Went out with him to verify we had the transducer set correctly and I was surprised at how grainy the Garmin side imaging was. You could still see structure and cribs and shadows but it did not come close to what my past humminbird 1198 produced or what my current Lowrance HDS Live 12 produces. If you plan to add livescope Garmin it is. If not I’d look at humminbird or lowrance for just side imaging.
I added a Garmin UHD73sv last year and feel let down by the SI images. Very grainy and difficult to see subtle bottom contours or fish. My Humminbird 999 has much better SI images, even when viewed only on a portion of the 9″ screen.