Darn! I saw this tread earlier when it was new and was going to spill out everything I knew, but that article above is basically where I learned it all! The thunder was actually very different than the dc01, no pre motor filtration for example and larger. I can also say that internally the dc02 and fantom lightening are nothing alike, with the dc02 having a far superior filtration system.
Nice find though! I have two like it, but earlier versions with 10 amp motors.