Advantages:  Inexpensive in small quantities and relatively easy to blend, do not require sophisticated equipment to load and may be used in a wide variety of resins (check with tech support.)  The best way to custom color rotationally molded parts.
 
Disadvantages:  The difficulty to disperse most pigments and additives will yield inconsistent results.  Airborne dust can cause contamination; required cleanup for hoppers, dryers and feeders.  Do not use in desiccant dryers.

Dry Color