The game was ok, like around 6-ish. It's less of a Castlevania game than I expected going in, and I wasn't expecting a Castlevania game. It is God of War 1 with much less polish, major pacing problems, and a different theme. Other than the throwaway references to old Castlevania games (this includes Gabriel's last name being Belmont), there isn't anything there that would make you think it was a Castlevania game.
and yeah, the frame rate sucks. There are a few times when nothing is on screen and it smooths out and it starts looking really nice. Then you move, the camera jumped around, because they designed it to be a disorientating asshole, and the game gets rough again.