So Flynn, if you are looking for a replacement for the core books, a way of fixing somethign you don't like in either 3.0 or 3.5, a cheaper alternative to them, or a way to help spread your name - then Edition Pi was meant for you. If you are looking for a way of playing sci-fi d20 or some other non-fantasy genre, but do not want to keep on using WotC products or want to try out somebody else's rules for a change, then Universal Decay was meant for you. Edition Pi has a very specific and relatively narrow purpose (a cleaned-up and fixed alterantive to the WotC 3.0/3.5 core rules, that still relies hevailly on those elements that actually WORK), and it does it and me an injustice to assume otherwise.