The key caps feel really nice. They are molded out of colored plastic rather than being painted.
Yellow's a bit green, but I'm ok with that.
Pink and Light blue are probably the best hues.
The deep blue seems just slightly purple to me.
The lighter colors, particularly white, have a semitranslucence that probably looks really nice with backlights.
lol ( and <3 ) at this site's awesome branding (and packaging).
Also, as far as I can tell, this is the only place to buy colored Kaihl key caps.