Still a SHW-M250x
This doesn’t turn your SHW-M250x into an I9100. – Your instructions change the PIT (internal flash partition table that is) and flash a ROM, like you can do it will all the other S2 as well, using all the other instructions.
The point is that the hardware is practically the same to allow such cross-model flashing. For more details: there is a SHW-M250x group here.
The most annoying difference between those models is: the accelerometer/magnetometer is flipped and turned by 90 degrees. So any compass/tilt software thinks your phone does something else than what it does...