I guess the specific question I have is, for my tzt3 to run PBG, does the combination of the tzt3 plus the dff3d and the pm488 transducer provide enough? From what I am reading, it sounds like that will get it working, but an extremal sat compass will make it work better from what I read the heave control is better in the external systems than the built in one of the dff3d? Is this true?