Originally Posted by Garry

The beuty of the SAM sytem based on S-300/Tor-M1/Su-30 is that it is MOBILE... i mean if we take time span of around a week..... and you can easily change its density where you want by adding more force where you need.

so you don't need to cover WHOLE 1/7th of the soil - the territory of Russia. You know from where your guests may fly... (not from North Pole direction) and you have higher density of cover in most dangerous directions.
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As for Supercruise

From my beer talks I learned that, unfortunatelly Flanker series would have inferior super cruise capability with AL-41F due to its sub-sonic optimization. While being more agile than most of fighters with comparable wieght it was made to be high maneurvrable on sub-sonic speed span and not supposed to fly long on supersonic speed.

On the opposite MiG-31's frame is designed to fly for long on super sonic speed.... if its engine could have been upgraded for higher thurst to weight it could have been somehow supersonic. But this comes at a cost... in close combat MiG-31 is not really as good as a Flanker/Falcrum.

From same beer talks, I learned what people at MiG think now about Raptor and Flanker. The Raptor's mock frame was blown in tube and they come to conclusion that it can not be as agile as flanker on subsonics.... as SUPERCRUISE costs you something - high maneuvrability. What I understood is that Flanker/Falcrum have their high meneurvrability due to somehow UNSTABLE frame.... which is not good for supersonic flights... it drags more on those speeds. Raptor/MIG-31/MIG-25 are STABLE and perfect for FAST supersonic speed.

So if I got it right... PAK FA designers must chose their own ballance between Supercruising capability and Subsonic high maneuvrability.