Pros
If you work for The SPS Division like I did, you will get a lot of experience very fast. Hopping from project to project gives you a chance to see what kind of companies you want to work for and what kind of work you really want to do. If thing get really bad a project you can ask to be taken off of it, which helps to save your sanity. Most of the time your manager at Robert Half is there to listen and you vent about things going wrong. They try their best to take care of you and talk to the client if something is wrong at the project
Cons
Most of the project I was on where ones when thing went bad or where going bad. I worked for two places where they just couldn't understand why no one would take the offer or why they didn't stay long in the job. The boss at the projects was hard to work and expected you to read his/her mind and this was some place where people didn't want to work. You are stuck there trying your best to deal with this bad place to work the best that you can, but it can be tough to be dragged in to the bad situation. About half the assignments are like that where you deal with places where they have high turn over rates and can't hire because no one wants to work there. The other half are much better short term specific project work which is much better. This is unforently part of the job of being a consultant. You are stuck working at the bad places.