In my unprofessional, patient opinion I have had all of them. Letters don't matter much. More schooling doesn't even matter much. Age doesn't matter, gender doesn't matter. Don't disqualify anyone. I did this once. And once only and he ended up being the best therapist I ever had. The only one who was able to reach me. I wanted a Phd, that was an older woman. I got her, she didn't work, then I got stuck with a young male with a LCSW and I spent months dreading every second I had to spend with him. Then we clicked and he fought for me till the bloody end. (aka recently).