Pros
You get to travel around the city meeting new people (both clients/teams), pay is better than normal full-times because you're a semi-consultant, although it can't compare to an actual consultant salary.
Cons
Managers tend to throw you in the fire no matter what technology you're interested in, and they oversell you to the client when you have no knowledge or prior experience of a certain technology stack by asking you to complete an online certification course in 1-2 weeks. Certifications are really not that difficult, but it becomes a problem when clients expect expert knowledge from you when all you have is what you learned during the couple of weeks. You also don't have much of a choice what project you get assigned to, and team/client you're working with can be a hit and miss.