The strength is in numbers, even if you don't "downgrade" equipment you sell, you better make sure you have a much higher number of the equipment for yourself.
This would not change the fact that a better equipped insurgency would result in a greater loss of life to the Russian forces than a less well equipped insurgency.

Based on what I have read in various articles from the United States Foreign Military Studies Office, the Russia-China relationship is only superficially friendly. Each country is taking advantage of the other.

For example, Russia is happy to let China buy oil from former USSR countries because it means those countries have no oil left to sell to Europe. This results in Europe going to Russia for oil.

http://fmso.leavenworth.army.mil/Col...AsiaEnergy.pdf

Are ordinary Russians concerned about the potential for future Chinese aggression?