SJ sells 3 models (+1 the one for childs)
I&C and X3 are pretty much the same, basically different offers. And the same as PJ.^^
The SJ prof is mainly produced in germany, made of Duralumin and constructed on a moulding cutter with high precision.
AFAIK the only parts that are not self produced, are (besides screws and stuff) the cuffs + bow, the clamp to fix the cuffs, the sole, the spring and the bearings (same as powerskips). That's why it's so expensive, although the value is much higher.. coz this frame is massive!

IDK who "stole" (copied sounds better^^) the design, but the basics for the design are even painted in the patent of alexander boeck.
So far.. any more questions?
