It's a bit of column A, a bit of column B - just in my experience. The building and playing with miniatures/terrain is its own reward, for sure. But with 5e, using them also changes the natures of the game - there are enough tactical rules that players engage in problem-solving differently, perhaps more mathematically, than they do when resolving combat through theatre of the mind. For D&D, I like the physical sets. For a game like Monsterhearts or Dread, theatre of the mind is the way to go, aside from basic maps, perhaps, to help players better visualize the situation.
Frankly, I find using miniatures and terrain almost the only thing that saves D&D combat encounters from being a tedious slog, at least for me.