Pros
McKesson is a large company with a relatively stable revenue stream in the Distribution Services business. The Technology side of McKesson can be a lot more chaotic, however the breadth offerings are unmatched in the industry. If they ever figure out how to go to market as a coherent offering, it could be unstoppable, unfortunately today the technology business is very fractured and often competes with itself.
Cons
McKesson is an incredible large and slow moving bureaucracy. It's essentially a holding company with no plans to integrate different business units. Almost all growth comes from acquisitions, and cost cutting usually involves layoffs, selling unprofitable divisions, or combining groups (and layoffs). Career advancement is very limited.