Pros
The compensation and benefits are competitive to above average. You get plenty of vacation days, there is interesting work to be done if your department lets you. It's not a place where you have to sit around to log extra hours in the office for appearance.
Cons
The main problem with Capital One is the professionalism of management. You really have to be on the lookout to see if colleagues are undermining you. I was floored by some of the discussions that I was privy to regarding both business and HR policies. There are absolutely no boundaries to what action someone will take. This issue is part of the culture at Capital One in general. They have put some additional controls in place since the early to mid 00s but it's still kind of a wild west type of place. If you get the right department and manager, it's great. However, there are just so many weak managers in general that at some point you're going to get a bad one.