A little secret is that Apple is having a bit of a problem with is the new SCSI manager. This is important if you use a third party (read non Apple) hard disk drive.
This new SCSI manager came out with the AV Macs. It is potentially faster than before and supports some really neat features, but if you use a non SCSI Manager v4.3 compliant formatter for your hard disk drive performance will be about thirty percent slower than before. This could be an issue if you choose to do one of the logic board upgrades since you bring your current hard drive over to the PowerMac machine.
If that hard drive happens to be an Apple brand hard drive, you should have no problems using the new Apple HD SC Setup utility. The worst that happens if you do not have an Apple brand drive, is it doesn’t work. It will tell you that it can’t find the SCSI device.
 
It also does not support multiple Macintosh partitions which can be a performance limitation with Adobe Photoshop.
Then you need to use a third part formatter to format your drive. The only one that I can find that is SCSI manager v4.3 compliant is from Anubis v2.52M Charis software.
 
I have been using it for about 8 months on the drives to be used with the AV macs. It supports multiple partitions which really improves the performance of Adobe Photoshop.
 
My one gripe about this formatter is that it takes a long time to format, test, and partition a drive. If you do the full test on a 1 gig drive it will take 90 minutes to do the whole routine. This compares to about 15 minutes with FWB’s Hard Disk Tool kit.
However, once the drive is formatted and partitioned, it runs about 20–30 percent faster than either LaCie SilverLining (v5.5), or Hard Disk Tool Kit (v1.31) formatted drives.
So what am I saying? The bottom line is that as a third party formatter for the AV Macs or the new PowerMacintosh it works, and I will continue to use it.