I have a Helix 9 on the console a helix 7 on the bow. I can see both well and I have had retinal surgery.
I also have a Hooh2 7 on my john boat.
I can't tell you which is the best. As they all have problems. When it gets hot (95 degrees) the hook2 shuts down. I have had the Helix 9 into repair twice now as it quits showing water temperature. And the Helix 7 is problematic in 10 to 20 feet of water and showing a double echo. I can mostly get around that by setting a bottom depth. But, truth is they all have/had problems. I can't write about Garminas I don't have one. They do make a great dog collar though!