Pros
You will be given opportunities at Seeking Alpha that can be career changing and you will be given an almost unending stream of them until you aren't. People fall quickly in and out of favor at Seeking Alpha so it is important to stay focused on the task at hand and not take it too seriously while you are on the rise. There is a strong and consistent undercurrent of drama and things often devolve into "us" versus "them" with the belief that if "we" could just get "them" out of the way everything would be fine. It's easy to get sucked into but if you can avoid that Seeking Alpha is an unparalleled place to learn and advance your career.
Cons
Seeking Alpha has a way of bringing out the worst in people. It definitely happened to me and as a result I have revisited my opinions of several former employees. In the end I lost respect for a few people that I had really looked up to and that was almost as difficult as coming to terms with the things I wasn't proud of having done while I was there.