Thanks for the replies, totally alleviates the concern I had. The set bonus for Sentinel are:
2pc: Reduces the rage cost of Vicious Throw or Dispatch by 1.
4pc: Reduces the cooldown of Frenzy or Valorous Call by 15 seconds.
I can do without both to be honest. The aesthetics are a large part of this game, so happy I get to continue with the orange gear