Pros
There is a nice campus, good benefits and you are working for the world's most well known companies. It can be a good place for someone in transition or wanting to build their resume with experience that will be noted for working at the most prestigious companies in the world. Some of the managers and trainers are really sharp, supportive and caring people and it can be a very fun place to work.
Cons
You are not working directly for these great companies, you are working for a third party. So, there is no job security or financial security. What you are told is not at all what you will have the opportunity to make. You never know what you are going to be doing or have the opportunity to make more than base. Base pay is ok, but you go in believing in commissions--they are terrible and sometimes you are placed in a position where you can't make commissions, you don't even know what your job is. There is constant change in your job and dramatic changes in your pay. I was hired for one job, came in after waiting for a month before the job would start, and found out I was in an entirely different job. I also had leads I was working, taken away and given to someone else, sales closed and then given to someone else (later told I did a great job and congratulating me for getting the sale for the team and I would get $5). I have seen genius pros go unrecognized; they promote people who are their pals and there can be discrimination and even hostile work environment. If someone doesn't like you for whatever reason, they can find one small thing and at any moment you can be walked out of the building. I have seen many people suddenly disappear from their desks who were good employees. The training is horrible and sometimes non-existent, even the managers didn't know how to do the job so no sense going to them. Final note, the place looks like a parade of circus freaks, tattooed, inappropriate clothing. They seem to hire people with "edge," so wear nice clothes going in but don't wear your nice crisp tailored suit. There are no suits there.