RE: The missile knows where it is...

The correct term is Redundancy Proof, seeing that s300 outperforms even patriot defense and all other anti air in range and destruction capability. Each target ideally is intercepted by two missiles. This system is for long range, not medium or short, and is Fully Automated and its capabilities exceed all other systems, stinger can't even match the speed of cruise missiles and needs a fairly large radar signature.

The S-300 is regarded as one of the most potent anti-aircraft missile systems currently fielded.[10] It is mainly used in Asia and Eastern Europe, including NATO member countries Bulgaria and Greece. An evolved version of the S-300 system is the S-400 (NATO reporting name SA-21 Growler), which entered service on 28 April 2007.

Its only exceeded by the S400 and they already have an S500.

Check this out:

Russian Anti-Satellite NUDOL Missile Is Frightening - Will Blow Any Satellite In Seconds

According to a Russian state media report, Russia’s first serial S-550 has successfully completed state trials, and it has entered combat duty. The covert weapon is reported to be capable of ‘striking spacecraft, ballistic missile reentry vehicles and hypersonic targets at altitudes of tens of thousands of kilometers. The ministry source told TASS that the S-550 air defense system has successfully completed state trials. The technology is allegedly far superior to Western and Chinese capabilities as an absolutely new and unrivaled mobile system of strategic missile defense. Recent Russian reports suggest the S-550 is the same weapon as a ‘satellite killer’ until now known as Nudol, a project clouded in secrecy. Pro-Kremlin Izvestia newspaper said it was part of one of the most covert domestic weapons programs ever conducted.

Say hello to Antey-4000 long-range anti-aircraft missile system designed to repel massive strikes

.Machine translation: Say hello to Antey-4000 (S-300V4) long-range anti-aircraft missile system designed to repel massive strikes, hit dozens of air crafts, helicopters, Tochka-U missiles, Bayraktar TB2 & reconnaissance drones.Max flight speed is 2,6 km/s. Max height of hit targets reaches near space - 35 km.