I'm a little concerned about my Power Mac G4 Workstation (G4/400, 320 MB Ram). It seems much more sluggish than either my iBook (G3/500, 384 MB Ram) or my iMac (G3/400, 256 MB Ram), which are all running Mac OS 10.1.5. Granted, the Workstation tends to have a higher workload than the others. But even at a fresh startup, applications take longer to launch, and Mozilla 1.0 has a harder time keeping up with my typing on the G4 than on the iMac.
When all the current projects die down, it's time to find a good defragger and find a good RAM tester. I think one of my DIMM's is seriously mismatched. :/