I am NOT saying that makers of fish finders are deliberately deceptive (though sometimes I do have to wonder) BUT if you are new to the whole fish finder/sonar/GPS thing, be wary (or at least, be very informed). A particular model may (or may NOT) have all the features you want/expect on it. And ESPECIALLY make sure it has what you expect before you mount it and or the transducer to your boat. Be especially wary if you read something like "this unit supports X, Y, or Z. This MIGHT mean that you have to buy an (expensive) accessory or different transducer in order for it to actually DO X, Y, or Z. Case in point, I was dreamily looking at the HELIX 12. This thing is massive but so is the price. I went on Amazon to compare their prices with the price I saw in the store. I found one that was less than half the price of the store model and I thought at first, "holy schneikies! What a deal!" This can't be right. I looked closer. I was correct. This one did not even have down imaging-let alone side imaging. Before you rush out and buy an expensive unit, do your research and behave a little bit like a (dare I say?!) skeptical attorney. It might save you some money or grief down the road.