To me just riding renders a sense of freedom. So whether sag or self-sufficient is not a critical question. I enjoy both. IT is just after a 100 mile day ride, why not pamper yourself. Same question as to whether we stay at the Hilton or Motel 6.
I will say the effect of 50 pounds swaying from panniers made me feel less 'bike steady.' And having to repair flats but first unload your panniers; I did not like that.