This is the most horrible bit of quality control I have ever seen.
I just bought a system today, went online just to see if I needed to update the firmware and discovered the complete lack of sense in naming updates and trying to correlate what my unit says:
System Revision: P020P05
I don't see any model number scribed on the bottom of my unit other than a serial number.
I would assume it is the latest and greatest but I can't even tell based on what is published on http://www.patriotmem.com/forums/showthread.php?t=2131