Him and his partner split on bad terms, if you google "the truth about TSS (two-stroke shop)" it's explains the falling out and the problems they encountered.
The guy seams to be very switched on about the stuff he deals with.
His project is now using an anthena top end with the stroker crank. The gearbox bearings and a few other bits all look the goods
I would love to build a rs500 but I just picked a rz350/250 for a project