You cant compare both imo. First of all both operate in different environments. Second, information regarding the solntsevskaya bratva and russian oc seems exaggerated.
For example these organizations are usually loose networks. Most of the time criminals unaffiliated with the bratva say they are to use their reputation. Which might be a factor influencing these inflated numbers. Also the connections they have with secret agencies and that they have former special forces among them is also known to be exaggerated.

I honestly think that most info available on the solntsevskaya bratva is fake as there are almost no sources to back them(wikipedia for example). This topic has been discusses before i think. ill try to look for the thread, it should contain some useful info.