I have a very nice Garmin Blue model on my MasterCraft now and plan on keeping it. After an incident with a stump and oh of course the alligator that decided to check out my wife I have to have one. However!!! I will not or can not drill holes in the transom of our new Moomba to mount an external transducer. I will order a thru hull transducer from Garmin (75.00 dollars) and install it in the location of the factory one inside the boat. I might even see if the factory transducer will work with the Garmin. Luckily for me I work with some Sonar geeks and they said if I take them boating this summer...............!