Get the Pioneer
The original "SuperDrive" is a Pionner. I suggest you pick up the DVD-R 105. It worked on my old G4 500 tower without a glitch. There is a newer version: the DVD-R 106 that has both DVD-R and DVD+R support, but I don't know if your MD G4 will take that, so stick with the 105: I assure you it will work if you are careful with the installation.