Basically, while valuable, combat experience is one of many factors that determine whether a military is any good:
In sum, experience alone doesn't ensure superior battlefield performance—a painful lesson the seasoned, but seriously deficient Iraqi military learned in the Gulf War. Experience is but one of many factors that contribute to combat effectiveness. Militaries that have mastered the other variables, as the United States did in the lead-up to the Gulf War, can more than compensate for a lack of experience. Moreover, mastery of the other factors can position a military to profit from its experience more quickly and thoroughly, a key attribute of high-performing militaries. ...
The PLA has likely improved its combat readiness from a very low level, but how much remains unclear. The persistence of corruption, concerns about the realism and rigor of its training, challenges in integration, and mismanagement provide grounds for skepticism. Moreover, given the PLA's history of cover-ups and prevarication, Chinese leaders have sound reasons to doubt the military's assurances of successful reform.
I suspect the Chinese armed forces aren't nearly as good as their shiny new equipment makes them look.
But China's military could be good enough to win a short "paint-by-numbers" war that China initiates according to a long-prepared plan before they have to wing it as an enemy reacts. The key for China would be ending the war after the initial victories over weaker and surprised foes.
And I worry that the Chinese who can order their military into action may believe their military is as good as it looks.
If the Chinese have an accurate assessment of their military, they'd look north to Russia for the target of a signal victory to announce their arrival as a great power.
