I can vouch for Tim, as he's done a bit of work for me on past projects.
He created the excellent cover art for Battleship Islands, as well as the UI assets for the level selection screen:
He also put together the mobile icon for my Win8 game entry - Neon Galaxy:
Thirdly as he's mentioned above, we both worked as a team on Hippo Trip for the ISR:
p.s. I'll update the official link as soon as our game gets published in early Jan on the competition site.