I don't and never believe that the Migs were all that superior to western type fighters.
The Mig-15 might had an initial advantage in performance and heavier fire power on paper. Yet the Mig was difficult to fly due to its Mid tail arrangement and when later models of the Sabres entered service the gap in performance was less significant.
Of course the USAF had better pilots than the Chinese and Nkoreans and a much better gunsight. The kill ratio speaks for this.
Still believe the Migs are better ? The Israelis got hundreds of them during skirmishes with their neighbours.
The Migs might be cheaper to buy, but suffer from old technology avionics and have low engine TBO, not to mention parts which are difficult to obtain for Russian aircraft.