I have. Never had experience with Alpine. I just don't like how you have to buy a deck and then spend extra money on the imprint, while other decks like Pioneer it all comes together in the deck. Also I heard when you use the auto EQ on imprint that you can't go back and manually adjust the EQ, ect...
your 780 should have T/A. my 7800 did, and i'm pretty sure its pretty much the same unit.