Pros
Lots of travel, good assuming you like it. Average pay and benefits. Great fringe benefits like airline miles. You are usually stuck in the trenches with likeminded coworkers, so you build team camaraderie and make friends quickly.
Cons
The mentoring/management system is convoluted - you get a random boss who doesn't know you, doesn't care about you, and doesn't spend any time with you. Semiannual reviews are like meetings of a secret society, and you have no chance of going anywhere if you don't know someone on the inside. Upper management is largely inaccessible. Avanade is attached to their partner Accenture at the hip, even though Accenture engagements are universally horrible and have high failure rates - but they refuse to cultivate independent engagements. Their other partner, Microsoft, is treated like a competitor - expect no help from them.