Well, the Pure Drive is a stiff and powerful racquet. Since the head is much wider than the ProStaff or the Prestige and it doesn't come around as quickly.
The ProStaff95 is much softer and more flexible. It is a control racquet. It doesn't have the innate power of the Pure Drive although if you lead it up it will still hit a heavy ball. In my mind, the Prestige is in the middle. It is(as all Prestiges are) a control racquet but because it is stiffer and heavier than the ProStaff, it has more power although not to the level of a Pure Drive.