Zimmerman uses mostly SLF dubbing - but I don't get too worked up over exact brands. I use SLF, Arizona, Ice Dub, Laser Dub - strand length, color, flash or lack there of matters a lot more depending on the look you're going for, and to a point, how well it stays in the loop.
Synthetic materials require dubbing wax to really stay locked in well, whereas natural materials compress and lock in a lot better without the need for wax. Personally I blend my dubbings a lot - mixing natural and synthetic materials going for subtle flash and mottled colors. I do like Jay's bright tail tips - I find that the more productive plastic worms I fish have a similar feature (pumpkin colored Dingers or Senkos with a chartreuse tail are money when fishing the gear rods)
The worms pictured above are using a mix of Arizona's simi seal, SLF, and natural fibers. I spin up the dubbing loop to the point where it's just about to break - once you spin it that tight it usually will not want to unwind to the point of loosing the dubbing, and you can furl it back over itself pretty easy at that point as well. I also do not do Jay's technique of hand furling. I have nerve damage in my hands, and THAT repetitive fine motor use would cause inflammation and pain in no time, so I use my Sheppard's hook tool, to spin the loop tight, clip a hackle pliers to the end of the loop for tension, slip the hook out, grab the midpoint with the Sheppard's hook, let it hang while I secure the end of the loop back onto the hook shank, then use the SH to furl the dubbing loop back over itself.
To get the variegated appearance, you stack the colors either in quarters or halves, and put the tail-to-be right in the middle of the dubbing loop. If you want more of a subtle mottled appearance, you can just alternate smaller tufts of dubbing colors all along, because when you spin it and furl it, you'll get shorter segments of color and a better mix.
I tie these worms up from tiny inch and half or so versions, upto a big 6 inch worm. The smaller worms work great for panfish, and bass will eat 'em too.