Are the Harriers in Iraq or Afghanistan operating from a hover and carrying any kind of load? Have they ever done so in combat? How does the Harrier like dusty hover downs? Guns like that of the A-10 are quite useful on people, machinegun emplacements, and other targets as well.
I think you'll find that the GR7s carry quite a significant load and have an advantage over the A-10 in that they are capable of escalating levels of weaponry. Also, the GR7 will fly significantly lower than the A-10 thus making it more effective for shows of force. Also, the serviceability and turnaround of the GR7 is particularly impressive.
Air to Air is not CAS thus not an issue. Thus far Al Qaeda only hijacks aircraft.
Can't argue with that one!