I have an older Garmin 76 and it does fine for me. I have it in a ram mount on the front deck and use the "yarn ball" a lot and turn off all other FF. Folks say they don't bother the fish, but I take no chances in shallow water. Throwing a marker gives bystanders the knowledge to come look after you're gone, and this eliminates that. Mine was a refurb from BPS in '04 or '05 and hasn't missed a beat. I also bought a hardwire for it and no longer feed the hungry beast a set of batteries every trip. It has gotten me home on a couple of tough days, fog can be a bear.
Creativity is just intelligence fooling around