Aside from what Ernst has pointed out, I would also like to point out that most pigment printers are printing on microporous inkjet receptor media. For best life, dyes should be printed on swellable polymer receptor media.
I make the distinction for a couple of reasons. First, even pigmented inks are susceptible to fade from airborne contaminates, especially ozone, when printed on microporous media that is not sealed. For this reason, it is strongly advised to frame prints behind glass, or laminates.
Second, dye inks can last nearly as long as pigmented inks when printed on recommended swellable polymer media, provided humidity conditions are relatively low (less than 40%, lower is even better). Dyes' short fall is incompatibility between certain dye colors, leading to premature failure when allowed to mix. In chromogenic processes, we had the different dye colors separated into distinct layers. Inkjet prints don't have that feature, and in heavy colors, the dyes can intermingle. With the swellable polymer technology, the droplets tend to isolate and not mix as much. Under higher humidity conditions, even the swellable polymer will allow the dyes to migrate and intermingle. Hence the problem with premature failure at higher humidity storage conditions.