Koetsu Std & the Koetsu Rosewood Signature

the std is a very good cartridge by all means. the signature version just takes it to a few notches above: more refinement on the mids, more open highs, bass about the same as the std.
I don't know whether its worth the extra $1100 ?

Thanks but if the specs are the same what is different internally.

the internal wiring, the slightly different body

What is different about the internal wiring.