Way back in 1972-3 in that other place, the accuracy of AC130's 105mm gun was the stuff of legend - the FAC could literally nominate which window in a building he wanted the shell in, and they could oblige. I think it would be a safe bet to say targeting has come a long way since then.
As for loiter time AND weapons load... you'd have to go a long way to beat a Herc. And the RAF already operates them.