I'd have to guess the Iraqis probably did not inherit the R-4x's ability to recieve command from exterior sources. If the MiG-25 had to illuminate the target with their own radar and manually command the missile into its terminal phase then its range was severely limited. The Soviet system theoretically could be used to extend the diminutive 25NM rating to about three times that distance. btw - There were two forms of the R-4x. The IR homing version R-46 and the SARH R-40.

Didn't an Iraqi Mig 25 shoot down an F15/16/18 in the first Gulf War with an AA-6?

IIRC it was a F/A-18C and the Pilot is still MIA(GOD BLESS YOU AND THANKS. WE WILL NOT FORGET).

Officially the F-18 flew itself into the ground to evade the missile attack. He was trying to cope with one of the slash and burn tactics used by a MiG-25. I don't remember hearing anything about the U.S. bagging any MiG-25's over Iraq, so it begs the question if whether or not the tactic would still work against today's F-15E or F-18E.

The truly sad thing about the Hornet kill was a Tomcat crew spotted the Foxbat on takeoff. The Tomcat crew could not raise the AWACS for confirmation to satisfy ROE requirements for a shot. The Tomcat continued forward with its package and the Foxbat was lost to continue its operation. It wasn't until sometime after the post-mission debriefs that two and two was put together. Or so the story goes... Shaken... out...

The Navy was pretty well cut out of the air dominance operations. The pretty boys in the F-15C's got all the glory even when the F-14's had several oppurtunities to engage targets. Politics.