I agree, a must have, ice fishing, or in a boat. There is no doubt they will help you put fish in the boat. In shallow water (<10 feet) - not so much - your not going to see fish, the cone is too small, but it will tell you whats going on, where the structure is. In water deeper than 15 feet I would be totally lost without one, you know when there is bait, fish, weeds, structure, a tree trunk, big rock.... Not only that, but after a while you will know if your looking at a small fish, or a big fish.