Cait is pretty good, as far as the companions go. I find myself once again rather disappointed that none of them really amount to more than a human backpack that occasionally fires their gun and likes to stand directly in front of you anytime you want to pick a lock, loot a container or shoot something.
After FO3 I was hoping to see better developed companions in Skyrim, that didn't go so well. Somewhat less hopeful for FO4, but the optimist in me was still anticipating seeing more depth to them. Well, I suppose they are better than the Syrim ones but none of them come close to my Rose of Sharon.
This is one area with Beth that the game is always so lacking making it feel just kinda tacked on compared to how grand and intricate the rest of the game is. They could make companions a great feature in their games, I really wish they would spend more time on them.