So then, how does the jet fare in live training missions? Any data yet?
Unfortunately, the performance and capability is (and will be) highly classified and you're really not going to hear a great deal in the public domain. Maybe a few throw-away lines; such as, "it's holding it's own against X,Y,Z" or, "in X missions we've seen great/average/poor success." It'll all be pithy i'm afraid.
I can say that those who are flying Operational Test and Evaluation will hold no punches in their assessments. Indeed, the feedback over the years at various OT EXCOMs from COMOPTEVFOR etc have swung from laudatory to scathing, depending on which area is being reported.