Finished it last night on Ultra-Violence. Played on PS4, took me probably close to 20 hours, being pretty thorough about exploration and getting all the secrets (had over 80% in one run). The game was at its absolute best towards the end, where you have all your combat abilities at your finger tips and the game throws the proper gauntlets at you to "Test Your Might" and see if you can keep up. Great final boss and one of the coolest ending credits sequences I've seen in a game.
Excellent stuff!!