There is one thing however, and as an engineer myself, I know it very well: No matter how good your scientists and how much money you have, you always need experience to make something good - and neither China or Russia has it. Watch the Nighthawk, it was very stealthy for its time, but it was full of compromises...So many compromises that were close to negating its stealthiness ! Iraqi...You remember them. They were clumsy - everybody says that. Both in the air and on the flak arena. First time the F-117 popped on something more serious than a 3rd-world country, it got shot down
In any case, the experience from F-117, money and the good engineers USA has, has produced the B2, the Raptor, the Lightning II....Things that are really fighters in all their sense - they fight, they bomb, you can fly them upside down and you can then go home with them. China has nothing. Up until the early 2000s it was a country with a great civilization in the past, but which was still stuck in Mao's 1950s otherwise. It
will be a decade before they can build anything that can counter the Raptor or any 4.5th-gen western or russian fighter. The most they can do is something a little better than the F-117 right now, I think. On the other hand, just look at the sheer size of that thing. This is closer to the 'Vark than it is to the Eagle ! Definitely not a fighter....And definitely not 5th-gen. Chinese industry is not mature or technologically advanced enough to produce really good AESA technology, or the extremely efficient RAM coatings of their western counterparts.
While I'm glad to see that they're able to build an airplane themselves, something which few countries in the world can do, this is not a stealth fighter and it's not a 5th-gen combat aircraft as well.