Pros
Worked on challenging and interesting projects, a lot of people when I started were very motivated and talented, most of those people left or were let go. Can gain knowledge, but don't expect much mentorship. Pay was OK, but not what I would say is in line with other firms.
Cons
Let go of or let top talent walk out the door, owner has very limited views of staff, especially staff who do not hold a masters or better degree. If you are hired as something, that is pretty much where you will stay. As I said, a lot of talent has walked out the building due to issues with the owner.