This is the first I've heard of such things.
You could do all kinds of things with the PCI Power Macs that you couldn't do with the early ones.The early Power Macs were great for the time, but I don't know that there's any reason to get one over a later Power Mac.
This is a useful guide to undesirable Macintosh models:
http://lowendmac.com/roadapples/index.shtml