I would go with the one you feel the best connection with...regardless of what their primary specialty is.

Our T, who we have been with for almost 8 years now, has some specialty in trauma/PTSD, children/teens, anxiety, and severe depression. We began seeing her for depression, and she diagnosed DID after 6 months. She has never directly worked with DID, but has supervised a few interns who have. This T told us at the time that she did not have experience but was willing to learn, and she was also willing to refer us to someone with experience if that is what we wanted. We chose to stay with her, and have not regretted that choice at all.