Tends to be much easier on single folks. Good friend of mine and I worked at the same place for a while, and he moved in to a consultant role, doing a lot of 'on-site' work with clients. Initial review, few days working with team toward goals, writing up reports, etc. He did like the pace - rarely worked on the same gig for more than a few weeks max - but travel really started to wear on him, typically around 80% travel. Definitely takes a toll on family life.