Eh, view those cost comparisons with a grain of salt. Something F-35 proponents have been fond of is quoting the flyaway cost of the F-35, against the total pr

Eh, view those cost comparisons with a grain of salt. Something F-35 proponents have been fond of is quoting the flyaway cost of the F-35, against the total procurement cost of legacy aircraft. They'll exclude all the testing, tooling, and r&d costs from the F-35, then exclude the procurement and support costs to finagle a unit cost number. Meanwhile, the quoted cost for something like a Super Hornet includes support/maintenance and some one-time costs. As for the F-15X order, that is to supply an Air National Guard squadron, which is currently using old F-15C/D's. They were not slated to switch to F-35's, so the idea was to just supplement with F-15X's in the meantime. IIRC none of the ANG squadrons are switching to the F-35 in the near future.