basically it's an all out race ecu from Mugen. No rev limiter...no speed limiter. More agressive fuel/ignition curves. Lacks an o2 sensor. It is a "race only" program that disables most sensor checks. The ecu is so rare i cant even find any more info of it online. Best bet is to probably call a mugen dealer such as "king motorsports" if your really interested in it. Here's a link of what i found online about it. http://www.pgmfi.org/twiki/bin/view/Library/XE5
Here's a link of people discussing it..
http://honda-tech.com/zerothread?id=842557