Pros
The people and pedigree. People at Bain are very intelligent and fun. The name on the resume will also take you far in recruiting for your next job.
Cons
The compensation. Out of college, most people who get job offers at Bain also get offers at top-tier investment banks as analysts. The exit opps out of both of these places is near identical. The downside of Bain is lower compensation in terms of bonus (particularly in an up-market); but the trade-off is the work at Bain is far more intellectually stimulating and I would argue you're better suited for business in your next job. Caveat: If you factor in their b-school package over the number of years, the compensation actually is the same as a banking base + bonus over the years. Not everyone wants to goto b-school right away, though.