]i got to use the 360 for the first time today. the unit that im using has no transducer other than the the 360. the only need for another transducer is to recieve the dept readings only. if humminbird would add that to the 360 it would be helpful. after only one time out with the 360 i dont think for me any how thats theres any reason to use di any more and only use the si on a limited basis