Which modem firmware for Samsung Galaxy S (GT-I9000) works best with the mobile networks in Russia?

Trying to use a Samsung Galaxy S device coming from China or Korea in Russia [lead to the observation that the quality of the connection to the mobile network is much worse](https://android.stackexchange.com/a/44021/13117) than on Samsung Galaxy S we used previously (which was bought in Russia). I have installed CyanogenMod 10.0 on the device in the hope that the mobile network connection quality would improve. But that doesn't seem to be the case. Now I see information that there are different firmware available for the modem; one should try to flash them to get modem working well in a specific region --: > Well, I guess you should flash another modem file, which is working > well for your region/carrier (use google . A modem file defines how > the radio part of your phone works, it has an influence on signal > strenght/network speed (and might have influence on battery life, > too). and lists a lot various modem firmware for the device. Which one to choose for Russia, Moscow (Megafon mobile network)? (The one that was working bad for us is XXJPK, and--on another device from China or Korea--SPJG2, which also has bad/unstable signal, but not as bad as XXJPK. After the installation of CM10, XXJPK on that device was replaced with XXJVT, which again has very bad signal.)