TyroneFly,

What types of dry flies do you want to tie? Broadly speaking, A.K. Best's comes close to Catskill-style dry flies.

If you like that style of dry flies, then, A.K. Best's is good. Particularly, I found two good things. First, A.K. Best is very passionate and engaging, so he will make you want to tie flies. Second, his DVD used so-called POV (Point of View) camera, so you can see the minute detail of fly tying exactly the way A.K. views the fly.