Yeah, at least I know v.4 is. I have a backup of the gameshark version4. What I do is use the CD swap magic to boot the gameshark then when it opens and asked to put in the game I put in the DVD swap magic and it works fine. Just make sure you have the codes entered correctly and the (M)Must Be On code (I made that mistake).
A little off-topic, but you can actually take a backup of one of these cheat devices and use swap magic to boot them up.
When I want my cheats to run, I use Swap Magic CD version to load up Codebreaker V7. Then after selecting cheats (when you have to eject, and swap the games) I put in Swap Magic, and boot up my backups.
