I saw an article on this topic on Warisboring and I thought I’d float it here.

https://warisboring.com/if-chinas-stealth-fighter-is-so-good-why-is-beijing-still-buying-russian-warplanes-16f189b74ba4#.kge8iabut

It’s an interesting point. It’s not like Russian planes are on par with the latest US or Western European fighters, if the J20 is as big of a deal as China is making it out to be, why would they be buying Russian jets?