I always loved Tekken more, because a good match between skilled players looked like something out of a choreographed kung Fu movie.
At least up to the PS2 era. It was also slower paced so you had to be more strategic. I always thought all the little character story movies were a lot of fun. SF feels very bare bones in comparison. But I stopped paying attention a while ago. MK had a distinguishing gimmick with the fatalities, but the general character design never meshed well with me.