Russia has, after much delay, introducing improved versions of its heat seeking air-to-air missile (the RVV-MD, also called AA-11, Archer and R-73) and radar guided air-to-air missile (RVV-SD also called AA-12, Adder and R-77).
It was back in the mid-1980s that the AA-11, a new Russian "sidewinder" type missile appeared. The AA-11 Archer entered service in what was then the Soviet Union, primarily being used on the MiG-29 and Su-27. The Archer had a range of 20-40 kilometers, depending on the version, and a 16.3-pound warhead. Among the features it included was an off-boresight capability (being able to turn sharply flight) directed by a helmet-mounted sight. The Archer clearly had eclipsed the AIM-9L/M Sidewinder, which had a range of 16 kilometers and a 25-pound warhead. The Python 4, an Israeli IR-homing missile, which also had a helmet-mounted sight, also was outperforming the Sidewinder (15-kilometer range, nearly as much as the Sidewinder, and a 24.25-pound warhead at Mach 3.5) Over the next decade, the Sidewinder was improved so that it could match the competition.
But the real game was with the radar guided missiles. The American AMRAAM was the standard everyone else sought to surpass. Even China got into act. The Chinese PL-12 was based on the Russian AA-12, which was the Russian attempt to produce a missile equal to AMRAAM. The AA-12 is similar in size and weight, weighing 385 pounds (versus 335 for AMRAAM) , 11.9 feet long (12 feet), 200mm in diameter (178mm). The AA-12 has a max range of 90 kilometers (compared to 70 for AMRAAM). The AA-12 has yet to be used in combat. Russian missiles, historically, have been less reliable and effective than their Western counterparts. The Russian missiles are not worthless, they are just less likely to knock down aircraft they are aimed at. The Chinese saw flaws in the AA-12 and wanted to improve that design so that it is more competitive with AMRAAM. The Chinese were eager to create an effective competitor for AMRAAM that they could export (they are already offering the export version of the, the SB-10, for sale.) The PL-12 has, so far, not demonstrated any extraordinary abilities.
The Chinese were also persuaded (last year, more by the threat of endless litigation than anything else) to stop stealing Russian weapons technology. Meanwhile, the Russians had been hard at work to upgrade their AA-11 and AA-12s, which were starved for development funds during the 1990s. The new versions are more "catch up" than "set a new standard." These versions are a little heavier, and have better electronics. They are also supposed to be more reliable. But additional improvements are in the works, as the Russians still believe they can surpass the American AMRAAM and Sidewinder. Meanwhile, the Russians mainly sell on price, because the American missiles have an impressive combat record (having actually shot down aircraft) which their Russian counterparts lack.