I prefer the classic look of the original Pac-Man to Ms. Pac-Man. I like the almost vector look of the blue outlined barriers in the maze and the solid yellow Pac-Man (as opposed to the gaudy looking Ms. Pac-Man sprite). The sounds are more classic too, to the point of almost being archetypal arcade sounds, as heard in many movies, TV shows and even songs. Also, I think of 80's arcades when I think of Pac-Man. I think of Pizza Hut when I think of Ms. Pac-Man.
Since I don't think any of the Pac games are much fun in the first place, the additional features of changing mazes/colors and roaming fruit are not enough to sway my opinion toward Ms. Pac-Man.
Additionally, Pac-Man is a bit on the fluffy side to begin with, especially when compared to the likes of Defender or Missile Command. The Ms. Pac-Man changes certainly didn't help it out in that department.