Like most anything in fishing the answer is that it depends. Face it, most all of the umpteen hundred million fly patterns that are out there are for us anglers and not the fish. i.e. I could fish the rest of my life using a dozen patterns (and probably even less) So I don't put a lot of stock in the color of the bead. But that's my opinion.
I don't think there's that big of a difference between brass and tungston either. If in the Smokies, your goal is to get it down quicker then I don't think the weight difference is going to matter a great deal - just use a split shot. If in calmer water, just throw it a littler higher upstream (which you should be doing anyway)
I have not noticed much difference between copper and gold beads either. One would think there would be a difference between silver and black, but I have a caddis emerger pattern I tie whereby the only difference is a silver bead or a black bead -- I have never noticed a difference on any given day between the 2 flies.
I would say to mix it up and experiment.
Last edited by Cane Pole; 08-02-2012 at 07:30 PM..