Ok, here's my two-penneth
Harriers GR7 regularly used to get 1:1 kill ratios against Dutch F16s on the ACMI ranges over the wash. WVR only as far as I know, and before you ask, that was reported by the F16 pilots and I was in the debrief!
Everything else aside, the Harrier is capable in a dogfight, but not exceptional, and in the end, as ever, it comes down to the skill of the pilot and the situation. Every fight is different, and everyone tries to engineer a situation where they're at an advantage before the merge (if the merge is the preferred option)
Truth is, saying "X aircraft can/cannot beat Y aircraft" is a simplistic point of view.