They're okay.

I got a sample pack to see whether the quality was on par with Sticker Mule's stickers and wasn't too impressed. They came out a bit rough around the edges and they're very lightweight (made of acrylic). I think they'd be best suited as a freebie gift for marketing purposes (not for selling your designs). It would be a dream if Sticker Mule offered an enamel version of the keychains/pins. Then we'd be talking!