Sony has not made an SACD player that did redbook well. Even my XA9000ES, which supposedly upsamples the redbook data to DSD, sounds better through a DAC. I would guess that you'll be happier with the redbook play with either the Marantz or the Cary. (Or, if you don't mind having two players, I hear the Rega Apollo is the redbook player to hear these days.). I wouldn't recommend mods to the XA777ES if improved redbook play is your goal. I had another Sony modded, and the sound was definitely improved, but retained the same sonic character.
Cheers.
Cheers.