Thats a nice series of flies, you've posted tonight Mark. I looked at the same article by Boyd Pfeiffer and bought the beads but never tied with them. Looking at this picture it may be time to tie them.
One other thing to try is glass beads. I've used the amber ones with the hole silver plated (rochailes ?) with good results. The sink rate is slower than a brass bead head and there real nice on wooly buggers for still or slow moving water.