Pros
Travel to different places. If you're lucky, it'll be places like London and Miami. If not, you could end up in a dead town in the middle of nowhere. Perks of gaining hotel and car rental points and status are great since you can use it for personal vacation and not have to pay for anything except food. Working at different projects is like working at a new job, which can be exciting.
Cons
Work/life balance stinks. They preach work hard, play harder, but it's difficult to do anything outside of work. Working 50-60 hours a week is typical, plus you have to put in the time for volunteer and leadership activities outside of work. If not, this will negatively effect your year end reviews, promotion, and raise. Do not get stuck with a bad counselor. He/she represents you during the reviews and if you have someone that isn't dedicated to representing you in a positive light, then kiss your promotion and raise goodbye.