I want to upgrade from my older Humminbird Fishing Buddy 120 to one of the newer high resolution models with downscan. It is going in a small 8' boat so am comfortable sticking with the relatively smaller screen like on the Lowrance Elite-4x. I don't need GPS. Right now I'm leaning towards the Elite-4x but only because I'm not sure if Humminbird or Garmin have a similar unit.

I see Humminbird has a 678c HD DI model, but it is bigger and looks like almost twice as much. I just want to make sure I'm not overlooking a better unit or value. Thanks for any recommendations!