I need to put new electronics on my boat and I am wanting to buy one good unit to put at the console of my boat. I would mount it on some type of rotating mount so that I could view it from the front of the boat also. I bass fish, as well as crappie, but most of the waters here in Arkansas are relatively shallow with the exception of maybe Ouachita or Tenkiller in Oklahome. Should I go with DI or SI? I am thinking something along the lines of the Lowrance Elite 7 with DI and GPS of the Humminbird 859 DI with GPS. What do you guys suggest?