I understand that the Marantz DV-8400 is based on the Pioneer 757, at least as far as the video section goes (though with an all new audio section). I have a 757 and am considering upgrading to the 8400 for better audio performance. I can't compare the two units side by side, so my question is will there be an improvement in video performance with the 8400? Are they totally identical in the video stage (same dac, deinterlacer etc) or has Marantz improved upon the Pioneer unit? I am keen for the improved audio of the 8400 but don't really want to shell out big bucks if it means identical video performance. Thanks.