RIT dye I have been happy with, but mostly I use natural dyes on my cloth and yarns. For instance you can get nine colors of dye just from onion skins, depending on what mordant (or none), that you use, which are lightfast and colorfast. Some mortants are as easy as using nails, cast iron, alum, ammonia (technically ammonia isnt), salt, copper pipe etc.
Tea and coffee also work, as does walnut hulls, grape leaves in the fall for yellows, yarrow and sage for greens.
RIT dye is the more reliable for the EXACT same hue each time, you are guarenteed to have different ranges with natural dyes, so if you want more than one article the same exact color, it needs to go.into the same dyebath.
Cedar