Q: What is the Difference between all the Wii mod chips?

A: Each Chip allow you to play Wii Backups, GameCube Backups and Gamecube Homebrew. They all read DVD-R Media. The Wiinja However claims a "stealth" mode where the Wii cannot detect its been modified. The Wiikey Does all that and also reads DVD+R media and it has the ability to be easily upgraded by the end user. Simply goto the WiiKey Website to get the latest updates (link section)