Depending on your personality and confidence you can balance your work-life in any way you want at any company. There is no work-life difference at any of the (big) consultancy companies. Travel policies are about the same, working hours are the same, etc, etc.
Only at the small boutique shops you will find different approaches.
I've worked 60-70 hours per week in hectic periods and done just 40 hours in the more relaxed phases of a project. And I have experienced this in several consultancies (MBB but also ACN, IBM, etc).
You'll not find a consultancy company that just does 9-5 (as a rule).