Whether you prefer one or the other largely depends on your gaming preferences:
you may prefer Whitechapel over Dracula because the absence of random elements puts more emphasis on the strategic aspects. You may also appreciate the fact that the game is skewed towards Jack, making the hunting players' task more challenging (although I believe long term players somewhat dispute this and claim the game is essentially balanced - It certainly doesn't feel that way to me, but I haven't really played it that often to dispute that claim). The larger map adds some tactical diversity.
OTOH, you may prefer Dracula over Whitechappel, because the random elements add some more variance. Even though the theme is reasonably well represented, Whitechapel may feel more "dry" to you, more of a "mathematical" exercise than a game. It can also be downright frustrating for the detectives, as a competent Jack player will probably be very difficult to trace, at least in the first few games, leaving the other player fumbling for clues more or less at random. IMHO, Whitechapel is closer to "Scotland Yard" in feel than to "Dracula". Playing as Jack, you may experience extended downtime as the game puts a lot of pressure on the detectives, who must carefully analyse and plan their moves just to stay in the game (incidently, this suggests that the sweet spot is just 2 players - It can be challenging to accomodate more than one Detective player, as not all players will be able to manage the frustration and complexity of the task at hand. YMMV).
My own personal preference goes to Whitechapel.