Not as enjoyable as the base game. Some bosses were well thought out while others lack soul.
Another issue is the game often will check mate you. Put you in a senario where you're guaranteed to take damage. The player does not have option to escape a series of attacks.
The inescapable attack scenario seems to be quite random. So it's a bit of a role of the dice if you're going to get a fair chance at beating a boss.