I traded my p112_p678 this morning for a p1404 and it's taking 3 hours, 50 minutes per percent on the G3/800. I also received a p1400 on the dual G4/800 and it's slow as well, taking 1 hour, 27 minutes which is being hastened by AltiVec.
I've got a p295_ that I've been working on for 4 days with a dual 2GHz G5 (although it's only on about 16 hours a day). I probably have another day and a half left on it.