all these cost assessments are numbers on a spreadsheet. let's see what the numbers look like after 20 years on the line, with SrA mechanics and most flight hours by new Lt's and Captains.
if they over-estimate the engine rebuild time, or if it really takes 2 hours instead of 30 minutes to remove and replace an avionics box (as was forecast), the calculation can veer in the other direction quickly.
i predict the F35 will be the most expensive by flying hour of any (line) aircraft that has come before it.
Right, that may well all be true, but the capabilities it brings to the table could still be worth it. I'm not saying I know the answer, but it's a lot more of an open question than I thought it would be a few years ago.