Sure the GR4 doesn't have a BVR capability (it's a BOMBER) but the F3 one is hardly credible! The Yanks would certainly wouldn't let it be used in Iraq because it lacks the necessary interrogation equipment. And why would they use the F3 with it's Sky SLUG or an AMRAAM with only a limited capability?
As for performance, I think that a GR4 in the same configuration as an F3 would be fairly even. Granted it does have slightly less thrust but it weighs less.
You boys do a good job making a fighter out of a bomber when history has shown that it only works the other way round e.g. F1-11, F-4, F-15. Who are you going to beat in ACM when the Italians retire the Starfighter?