Dharma Fiber Reactive Procion Dyes

Pro's: Best dye for cotton, rayons, linens, hemp and other plant based fibers. Best dye for Tie-Dye and Batik. Vibrant wash fast permanent colors. Easy to use. Does not need hot water. Economical!
Con's: Colors are still vibrant, but shift on silks and wools. Need to use with the proper chemicals. Do not work on synthetics.

Dharma Pigment Dye

Pros: It's a concentrated (so economical after dilution) pigment system that feels like dye instead of paint, is easy to use for all kinds of techniques, is concentrated, non-toxic and works on most synthetics as well as natural fibers
Cons: Limited color selection, colors fade with washing the first time (typical of "dyeing" with pigments) - you have to like the unique "stonewashed" look