FWIW you can install a total of 3 internal drives into your G-4. One above the current drive that is ATA bus 0 slave, and a thrid in the slot where the zip bay is(under the DVD/CD drive) that is ATA bus 1 slave. For firewire, we built our own firewire dock (colplete with Oxford 911 chipset) with 2-40gb drives(you can put any drive size you choose that is available) for under $300. Want a hotswappable firewire dock with 2-40gb-60gb drive docks for under $300? check this link: It describes the drive for use with a Mackie HDR/MDR, but you can get drive bays, and use it as you would any other drive. Get the dock from here: Get the carrier and drive trays from here: You can also get extra drive trays separately from them. The enitre unit takes about 30 minutes to assemble, is externally powered so it doesn't draw from the firewire buss, and is about the size of a medium hardcover book. You can put any ATA drive in it, and if you use PT approved for recording drives you can record directly to it from PT. You can put together the drive dock and two 40gb holders for under $300. Each add'l carrier and 40gb drive is under $100. The drive carriers are hot swappable. It is universal voltage too as I recall. If some of those links don't work jsut e-mail me directly and I'll get you ones that do. Hope this is helpful.