Whenever you're dealing with something expensive and single-buyer, you're going to see quibbling and politics. There's a reason the export market for US arms tends to be the lower-budget stuff; it actually has to compete on the world market against BAE, Dassault, Sukhoi, etc. That's why we're still making F16s.

As to the Israeli modification bit, that was speculation on my part based on the fact that the Israelis almost never buy or fly stock gear. They even fuck with F16s, one of the most bare-bones, straight-up general purpose fighters ever built. Will other countries be able to wield such changes? No idea. Not sure other countries will be able to afford F35s. The flyaway cost of an F35 is likely to be somewhere a little south of $200m without subsidies, in which case who knows? The flyaway cost of an F16, by comparison, is around $20m. In other words, one F35 is as much as a squadron of F16s... or a flight of Sukhoi Su-35s. But that's okay- Israel receives more military aid from the US than all other countries in the world combined, and they're on the docket for 75 of the things already.

Now would be a great time to watch Deal of the Century.