@Ninan No personal experience, but I have read a few patient testimonials about this doctor, and interviews with him. I haven't heard anything really positive from PWME, when they went there specifically to get help for ME. It's a different story when you have a differential diagnosis of something hormonal that could be treated separately, cause it looks like he has made quite a name in the hormonal field.
He's a little bit obsessed with 'eternal youth', which is why he has been taking growth hormone himself for many years. (He does look a lot younger than his age, so it seems to be working!
) He says that his focus is not to cure, but to give better quality of life.
From what I've heard (and again, this is coming only from patient testimonials) he runs a thorough blood panel, and prescribes a LOT of things in one go, which usually boils down to a combo of growth hormones + something for adrenal insufficiency which he seems to deem necessary for many/most PWME. He also adds supplements and diet/lifestyle advice to that. The ME patient testimonials I have read weren't great tbh. Maybe too much/too agressive for a sensitive body? It also seems difficult to get off the hormones once you've been taking them for a while.
By the way, his sister is also a doctor (internal medicine) and also has a practice near Brussels. It looks like she follows a similar diagnostic routine, but I haven't read any testimonials from her patients.