I think who you follow is purely a personal thing, which is why I hate threads where people ask which NH trainer is best.
I'm the opposite of HorseCrazyTeen as I follow the Parellis and find their programs much easier to understand.
This being said, I have looked into Clinton, Buck and a few others and actually went so far as to order DVDs (though Bucks were borrowed lol) but I will prefer the Parellis. Nothing against the others, though, I got many tips from them all.
The Parellis, however, do not have many training videos on the internet and if you truly want to grasp their methods and concepts accurately and in depth, you have
to order the DVDs, which can be pricey. Even the books do not give a clear idea of what they are on about, and these are the reasons I believe many people don't like them. The free/cheaper info that they have out there is not
very good or helpful.
And they have many DVDs, so for me it helps that I have a friend who is a member of their Savvy Club who gets the DVDs herself and then I just borrow ha ha That way I know which ones to get that are the most informative ;)