[Right on Q]

I'd say it depends on what your objective is. If you have a base knowledge of competition bbq I'd say Tuffy, Travis Clark, or Pellet Envy. (I've heard great things about Donny Teel's class as well)

If you're trying to get a base knowledge of comp bbq before you progress to more advanced classes, I'd suggest the Kosmos Q Dvds or any class local to you.

If I had to pick one general answer for everyone I'd say Tuffy.