What concerns me about the F35 is this. Should the Russians or Chinese suddenly develop a tracking system that makes stealth redundant, what are we left with? In the case of the F22 it would still be the premier air defence fighter in the world. I am not really sure what the F35 would do any better than the latest fourth generation aircraft.
There's been talk about that for decades. I used to be skeptical about stealth capabilities, but it's been proven to work. It's not impossible to locate an aircraft, but the general idea is to make it very difficult. It's always possible to track something visually or based on its heat. However, isn't the major of air combat these days based on radar guided missiles? When you've got something with that little a radar signature, what happens if a missile loses track?
The other thing about the F-35 is the advanced electronics. I think they call it "data/sensor fusion", where it doesn't have to be a self-contained. It's supposed to be able to direct weapons from other assets that are airborne or on the surface.