embarrassing if a dogfight ensues and Russian Planes get knocked out of the sky. as happened during War of Attrition along Suez Canal few decades ago.. Also it could be bad for Russian Weapon Sales if the S400 and S 300 dont live up to the manufacturers claims!...The only hope for Syrian Air Force is to shoot down Russian Plane and then Russians can blame Israel and Gen Suchoi can wade in to Israel IAF staff in Moscow.