I've read both good things and bad things about him. Supposedly he's very expensive but has had success with some difficult cases, especially Lyme. He offers a wide range of treatments, but I don't know how much experience he has with ME/CFS.
His claim to be able to diagnose all that ails you from a single drop of blood is, to me, lacking in any credibility. His site is so reminiscent of many "maverick" doctors, and perhaps goes even further.
When people don't feel well and the medical profession doesn't help, I think there is a tremendous allure to doctors like this who claim to offer diagnostics and treatments that others don't. And they seem to have mastered all the buttons to push. I am vulnerable to it myself sometimes.