I'm not really sure what maintenance costs over that period in a contract look like: certainly getting them down to a number introduces a bunch more risks for someone (inflation etc), and not having them has other risks. Getting numbers here is sadly hard, and I agree my comparison might be not apples to apples.

Even if the flyaway cost of a Grippen is $50 million the number of planes to accomplish the same mission is a lot more, and some of that number will be lives lost. I'm pretty confident it's within half an order of magnitude of F-35 price.