Many questions after reading you...
1st: are those modems for i9001 or for i9000?
2nd: I must choose an XX one cos im spanish, but which one? what are the differences? I have CM10 installed in my device.
3rd: which are the steps in order to change modem?
My baseband is XXKPG
Kernel: 3.0.74-cyanogenmod-g8b3fc54 tiziano@tiziano-ubuntu #195