HH - An interesting scenario, particularly since BAE/RR would retain their workshare (US- and UK-domiciled) in JSF.
FA-18 - The trouble with "no one can honestly predict" is that if you run an AF you have to try, in order to engage in rational planning. It is not impossible but the answers will vary from nation to nation, and it does require integrity and non-fantasy predictions. For instance, if the annnual R&D bill for F-35 upgrades is even half that of the F-22, and if we get quickly to a 1000-jet fleet, then each jet still carries a $500K/year assessment - $2-$2.5K per flight hour right there before you pay for individual mods. And those are mature and optimistic numbers.
And with this many a/c on order, this many hours flown and 12 years into the program, to say that we can't predict operating cost is damning.