Apparently prior to getting their hands on a MiG-25 from a defector who took one to Japan, many in the western military and intelligence communities envisioned it to have super avionic powers (that persisted for a long time in the civilian sphere). They thought it was agile and fast. What they didn't know is that it could only sustain those speeds for short spurts (else the engines suffered from metal fatigue due to temperature) and the maneuverability they envisioned from the geometry proved to be false (it had a very wide turning radius)...