As far as GTA knock-offs go The Godfather actually wasn't half bad. It just became very, very repetitive especially from about the mid-point on. Granted, I took over literally every racket in the game and ruled the city completely but it was 40 hours I (more or less) enjoyed.
That being said, I have little reason to believe these guys can do a quality System Shock. But then again I never played the first one and hated the second one so maybe I'm not the best SS authority 'round these parts.