I dont use my finder for anymore than to see the bottom contour and bait balls and then i fish that area. All the other markings dont really mean musch to me. A friend of mine has a colored finder and yes you can distinguish your fish alittle better but still at a 150 ft do you think a 6 inch fish will show up I dont really know. This is the same goes for Radar how many times have you came up on a fiberglass boat with a inboard and were caught off gaurd when you are running it at say 4 mlie range.