Probably keep it around a bit longer. But I kinda doubt the manned fighter has much life left in it. Between the drones, avionics advances and the ability to let a computer think for itself, one has to wonder when the air above will be full of drones doing the job with people in an advisory capacity.
When you consider the cost of an F22 making the production a limited event, it is possible for the signature of every F22 out there (what there is of it) can be stored in a computer and the drones just go hunting for them in a time of war. Consider a stealthy drone out looking for a stealthy manned fighter. Odds favor the drone. It doesn't get tired or bored and is indifferent to it's own survival.
I think the same situation is going to stand in for Sea Power. Why make a sub when you can make a semiautonomous torpedo with the signature of the ship(or ships) it wants to kill stored in it's memory banks. Turn them into mines, drop them in the enemy's home port waters and....
Sorry for the thread drift.
Silent Eagle is a nice bird, cheaper and given the sensors, maybe a good call. But if the Eagle can get stealthier, so too should the Raptor.