I'd say that PT is the better game BY FAR! Much less aimless wandering, *many* more opportunities to role play, less linear story, and the story (I find) is totally engrossing! And, if you relly like the hack 'n' slash, there's plenty of that too, but you're not forced into a lot of it.
Black Isle did a first class job on this game, I bet you're gonna LOVE it!