I got pictures of a dark keycap with yellow PC. sorry guys, it's a no-go. The legends are not visible in daylight.
No worries at least it got us excited about having it done for a very short while.
Still happy you're offering SA and DCS with this and it should be your last key-set designed for all fellow Geekhackers. We shall be there to get these when they pop up at SP Group Buy section.
You may even call them Matt3o's Goodbye Midnight Set
. I'm sure it will be very popular as everyone jumps in to get an artist's last rendition of his work, like a Picasso, Dali, Duchamp or Chagall.