Ebay Eldar (GBP 2.29 + postage), before and after Minwax Tudor dip:
They are certainly darker, and the colors look less like "beginner's paintbox".
Terminator, dollar store acrylic and dip, no undercoat, bare red plastic:
The skull and crossbones clearly shows the black dye in the Minwax Tudor.
And some Tyranids painted properly: