I dropped it into the G4 on my SATA card on the PCI Slot (Sonnet 2-channel SATA 1.5GB) and it's running great. boots as well!
it's wicked fast too!
The CDs burn at 56x, the CD-RWs burn at 24x, the DVD-+R's burn at 16x, the DVD-+RW's burn at 8x, and the +DL burns at 6x (I guess there are no -DL discs or something... All i have been able to find is +R)