The GTR thing makes sense, but 2 x WBO2 kits is getting a bit exorbinant, my only other issue would be with comparing the accuracy.
It says it's setup to emulate a Bosch LSM-11, what do Skylines run by default, and how close are they to this?
My guess would be there's not much difference, and that it shouldn't effect the car much, but if it did you'd notice the shit fuel economy pretty quick!