I had wanted to dye suede before a shoe repair shop told me it could be done but it change the suede to normal leather can not recall if they said nu buck or smooth. I think if they look odd at all...
For a colorfast tie dye a fiber reactive dye is needed such as Procion Dye from the Dharma Trading Company. Rit dye can be used but is not fiber reactive and not colorfast and the tie dye will fade...
No. It is a synthetic fabric, brushed microfiber Polyester. Nice look, have two ivy caps made of this material and they are machine washable. About half the price of suede caps.