I think it is a question of what you can afford in terms of time and $$s.
It was my experience that every course I attended had within it some important element/s that the others somehow missed out on. Many times the content of the courses directly contradicted "facts" I had been taught elsewhere. There is also a fair amount of "selling" going on at each of the courses, be it of still equipment, or barrels, or insurance, or glass/corrugated, etc. but it is rarely too much.
It is difficult to say what the "best" course is as they are all very different, and it depends what you are wanting to learn; distillation, fermentation, business skills/plans, marketing, sales, TTB regs, tasting, etc, etc. some of the courses claim to be for beginners, but without at least a basic knowledge distillation they are sometimes way above some people's heads.
As some folk have already said, the most useful "course" I did was to spend several days at a distillery getting some hands on knowledge and being able to talk directly to a distiller without 30 other people trying to get their attention.
However, I only did that once i had attended several "theoretical" classes to understand what the process what all about.
Another fantastic thing that came out of it all was meeting like-minded entrepreneurs on the same road, some of which have become firm friends and the collaboration between us for information and advice has been invaluable.