Pad work is extremely overrated IMO, it does have a use but it should not be overemphasized. The countless rounds that a boxer spends on the pads could be better used for drill work and situational sparring. Doing drill work with another boxer will better develop the skills that you need in the ring. From what I have read, this is how the Cuban's train (little pad work, emphasis on drill/sparring work) and it is clearly working out well for them.
pro's and cons aside.. hittin the pads is my favourite part of bein in the boxing gym apart from sparring.