I was under the impression that the ITER was an experiment that would run for the most a few seconds. I don't believe Lockheed. To my knowledge no one has ever achieved more than a second and no one has ever pulled out more energy than they used to get the damn thing going. It seems to me that physicists without a financial incentive are crazy cynical about it. Could somebody make it work? sure. Is it likely? I don't think so.
It's true that ITER's goal is to achieve 500MW reaction sustained over 1000s. That is because the dynamics of large scale tokamak magnetic confinement need to be more closely studied, as well as evaluating strategies to contain the high energy neutron emissions from the reactions. But if those goals are achieved, then a large reactor with a continuous reaction will be built shortly after. That's the whole point of ITER.
It's not exactly true that nobody has pulled out more energy than they put in. That was achieved by NIF last year, if only juuuuuust barely.
Lockheed may or may not have made a breakthrough. The problem with academic labs is that they are relatively underfunded. I think there is a chance that a private company can crack a commercial design before the scientific community. But since Lockheed is supposed to unveil their reactor within the next couple of years, I guess we'll soon find out.
From all I've read and heard, I think fusion energy have a very high chance of being commercially viable within the next 25 years. But I don't want to play the game of probability. We'll know more in the next decade.