I loved it for it's lush graphics and robust combat mechanics. Though the story suffers from chore-like activity early on before the action really kicks in from "The wild one's".
It really depends wheather you can tolerate it's backdrop only to be served as a story driven arch than free roam incentives as the story is choke pointingly linear. It's bettered dlc (for me) was a motive to revisit Empire bay in acceptable gta form.
If you're choringly half way through the story, particularly without it's dlc's, i'd say keep at it, as the sheer experiece is class for the mobster genre.