Toby had three sarcoids when I bought him.
Personally - ducks head - I had no intention of using the highly invasive and incredibly painful and expensive Knottenbelt procedure.
Over a course of a year, using Sarc Ex and allowing my horse to build up his immune system with Immuplus as well, he is sarcoid free and has been for over a year.
In my opinion, and experience, sarcoids are caused by a low immune system and generally occur in horses that have moved around a lot and are stressed. Toby had several owners in the year before I bought him, and having tracked his owner down who had him from a yearling, he certainly wasn't born with them, but between years three and four - when I bought him, he had several.
Once you have the immune system kicking in, and a less stressful environment, I believe the sarcoids will go.
Clearly you will do what you think best, and if you think the Dr Knottenbelt way is the best option, that is what you will do, but you have only had him a few weeks, and I personally would let the dust settle before starting on any course of treatment, and certainly try a less invasive and painful way first. After all, he has lived with them for some time clearly and is in no pain with them.
Vets are very much like the rest of us. My own vet, who I have a massive amount of respect for, and who specialises only in horses and spent some time in New Zealand where they have nowhere near the amount of disposable cash to kick around, said that his girlfriend put their horse on a '
herbal diet' - and it sorted the sarcoids.
Many roads to Rome I guess. Just depends which one you choose and how quickly you wish to get there and by which means.