Every drug works different for every person. I think we can all testify to that. I love Trileptal, some people here say it was the worst for them. Wellbutrin works for me, for others it makes them manic. Lamictal seems to work for most people, for it me it was horrible. There is no way to ensure what works for someone will work for another.
And I haven't come across any research that ranks drugs. If it were that easy, we wouldn't have as many problems as we do. IMO it comes down to the pdoc's experience, your symptoms, and your medical history.