Nick and SAS,
I'd counter that to the USMC, the Harrier is a good airplane. I don't dispute that they gave a bunch back in inadvertant recycling, but the Corps certainly seems to like having them around. So, to use the AV-8 as an example of a 'flawed' piece of equipment did not add to SASless's arguement.
And to the V-22, I don't have an opinion on it, yet, regarding its OPERATIONAL success/failure history because it doesn't have one. Just because its development history has been tedious does not make it a turkey.
It may very well be said bird, but its too early to say yet, IMO. Very few a/c development projects, particularly when as challenging as the whole vertical to horizontal flight thing is, have gone off without much wailing and gnashing of teeth.
Again, whether the USMC really wanted the a/c is another, political, matter that the congressmen from TX decided.