Pros
You develop a close working relationship with some of your coworkers.
Cons
I was a former employee of the SI and got laid off due to cutbacks. The company did absolute nothing to place me on another existing contract, or furlough me until something else came open. During my employment, I continued to apply to positions with the SI., only to receive the "canned" email from the "talent recruiters", in which they tell me I am not qualified. EXCUSE ME! I have more than 24 years experience and a Masters degree in IT! Oh and BTW most of these "talent recruiters" only have a HS diploma. Interesting! Or, if one of them did call me back, they would ask for my salary requirement. I would tell them my expectation which was completely in reason, only to be told "oh that is too much money....this position only pays 100K." To which I would reply, "then you don't want a Sr. Systems Engineer, you want a college intern." I found a company that recognizes talent and is willing to pay for it, I couldn't be happier. Long story short, this SI is poorly managed company with short vision. Good for interns...maybe. Good for season experience employees, NOT.