I only fish the western basin as well. Did a lot of research when chosing a sonar/gps combo and at the time the Humminbird was my choice. I think it's simple to use and I really do like the 3d sonar when locating structure and the few times I troll. The Lowrance HD units weren't available when I was looking or they would have been serious contenders when making my choice. While you make your decision make sure you research the transducer options for your boat. I would imagine you would probably be going with a shut thru hull or a thru hull. I just got an extension cable for my transom mount transducer and use that. Works fine trolling or drifting. doesn't work well while moving above roughly 5mph.