I am looking for a fish finder for the front of my boat. I want to mount the transducer on the trolling motor. I know that SI would be best but because of the price they are out. I have read all the pros and cons about Hummingbird and Lowrance. I would think that the wider the cone the better it would be. Eagle fish finder model 245 DS has a 60 and 120 degree cone, The Hummingbird model 160PT and 170 both have a 60/20 beam.I am fishing shallow lakes in nothern MI. NEED HELP!! Thanks