As long as the PAK-FA and Russia are dependent on stealing technology and/or copying other aircraft and technologies then they will always be at least 11/2 generations behind the USA and other western nations. Russia doesn't have the money or the people, China doesn't have the technology or people and they both have significant internal issues.
When the next Microsoft, Google, NASA type probe, Boeing or Aerospatiale Type Company, innovative microwave communication device or other new technology, comes from Russia or China, then and only then, will there be a cause for concern. I cannot see that happening as to develop an F22 type aircraft you need to blend a lot of technology with one aim. Having one piece of the puzzle is of little benefit.