Well, ORAC. big deal.
Not sure about your experience making intercepts at 1.3M or above, and ditto for combat experience. Profile is lacking on those details.
Fighter Controller for nearly 25 years. Three main reasons I found essential for fighters going supersonic.
1. To get to the fight, whether to achieve a cut-off or in a tail chase.
2. To get out of a fight when bugging out.
3. To be able to trade speed for height either to ID a high flier or to achieve a snap-up.
Most important being number one.