My cousin just moved in with his nice 17' Tournament Cat fishing boat. We hit the lake last Sunday just to mess around. The boat is great, but his fish finder isn't. It has a real small screen and you can't tell much about the bottom or if you are looking at big fish or bait. I'd like to get him a good depth/fish finder but I don't know much about them. What would you guys recommend? What kind do you have and how do you like it?