I had worked for Manpower Temps in the past.
Pros:
*You gain field experience especially if you are new or returning to the field
*Sometimes, temp jobs can become permanent (one of mine did)
Cons:
*Benefits and perks like taking vacation time only come after you are with the the agency for a certain amount of time (also depends on the agency)
*You never know where your next job assignment is going to be or if there is one available.
*Not a steady income.
*Hourly rate varies depending on the assignment
When I graduated from a business school in my 20's, I tried to go directly into the secretarial field immediately. I didn't do so good and lost jobs due to my inexperience.
I then decided to do temp work. That helped me gain experience and show me how different companies work. But then, the assignments started to slow down and I tried the full time, permanent work. I still wasn't ready and decided to go back to temping. The last temp assignment I had led to a permanent position with a very big and well-known company. I was there for 7 1/2 years when it was announced that our office location was closing

.
I did find another job but due to the company's financial difficulties, I was laid off (as were 7 others) last year. I would not be able to do any temp work now, b/c I'm in my late 30's and have a family. It's not a good fit now compared to my life in my 20's.