Questions about diffusers

Hey. I have two questions about diffusers.

1) Bigger or smaller holes influence on the smoke? Which one is preferable?

2) How about the number of holes. The more the better or what?

well, the point of a diffuser is to have many small holes in contrast to one large hole.

larger holes allow for an easier pull, but smaller holes will filter out ash more effectively.
Many small holes is preferable.

You got it bro, more is better. See the "bong school" link in my sig for more info.