I’ve been watching your post. I haven’t used one of those so it wouldn’t be fair for me to say.
There’s really only a couple “in the store” test and that’s having a Marcum next to another brand and point both cameras at something bright. Like a red jacket about 10 feet away. Look to see which monitor shows the closest to the actual color.
Then look what can me seen at the edges of the screen. You’re looking for field of view. Which one shows the most compared to the other. Some companies use the “fish eye” lens to get a larger field. Is the picture distorted? I like seeing what I’m seeing and not an artificially enlarged fish.
Find out if you can take the camera outside to look at the monitor. How’s the picture in bright sun? If you fish in a house all the time, this is not a big deal.
But one of the most important features of an underwater camera is if it can see in the dark. I’m not talking about muddy water. Just dark water.
Most ice guys end up fishing at night. Most any camera words adequate during the day. If you fish at night for in +30 feed of water and the camera monitor has the “snow storm” effect it’s garbage.
Then it’s time to look at the Marcum line of cameras. I’ve filmed in 50 feet of water and it’s as clear as looking in a mirror.