Having known Birks for the last 30 years or so I can say he is one of the most genuine and knowledgeable trials enthusiast I have had the pleasure to know.
In my experience of visiting a good few world rounds over the years all the other "superstars" are very decent human beings I can think of Mart, Malcolm, Dougie, Grimbo, Eddy, the Steve's (Saunders and Colley) to name but a very few.
I think we are lucky to participate in a sport without the mega ego's that exist elsewhere.