I would like to see on paper how the replacement for the A10, the F35, is going to accomplish the same mission with the same survivability. The number one threat to CAS aircraft is and likely will be for a long time is AAA. Guns. Next down that list is Manpads. Two systems that Stealth and whizzy expensive technologies the F35 will be using won't help much against. Especially manapds that are optically/laser tracked and targeted.
I wouldn't argue the point that on the first day of war vs a well equipped enemy, that the F35 is likely to be more survivable in the battle space than the A10. It's just what comes after that I'm concerned with, after the C3 and enemy's eyes and ears have eaten HARMs and other missiles and are gone or greatly degraded. In future wars that end up being similar to the wars of Afghanistan and especially Iraq, then having aircraft like the A10 around, which is cheaper, faster to turn around and maintain, and more survivable to the remaining threats of AAA and Manpads - then I think it would be greatly missed. The F35 doesn't have the loiter time or systems and weapons that are specifically made for the CAS mission, plus it's a very expensive asset to risk down low at those altitudes where even rifle fire is a potential threat/risk, much less dedicated AAA systems. I'm not saying the F35 won't be a good system for what it's built for, but I don't think anyone ever envisioned it to be taking over the A10's role, so unless the A10 no longer has a role (ha ha), then I don't see how retiring the A10, whatever the costs involved, is a good decision. Just my opinion.
Regarding $, the Secretary for the Air Force and his top 3 Generals have all said that the A10 program will save them tons in overhead and costs. The recent numbers are 1% of the 110,000,000,000 of the yearly budget for the AF, and those A10 savings will only be programmed for the first 3 years after it being retired. Doesn't sound like a pile of money to me, considering the lost capability.
One solution I think that would work great - the Regular Force Army has said it needs to take the AH64 Apaches away from many Guard units due to the budget and cuts and so on. Ok fine. Why not replace those lost Guard Apaches with Air Force A10s? Move them to the Guard, they've already said they would LOVE this idea, and can figure their budget out to do it. Of course, the Air Force will say they don't need the A10, but they won't want to give it up to the Army either, and lose control of the CAS part of their budget, but I would hope somebody up top would say too bad, you gave it up, now it's going to be used by units more invested in the ground game to begin with.