The PWC office near Embankment?
Depends of course if it's Z3 west, east, north or south.
If you were living in Gunnersbury or Wimbledon it's probably about 30 minutes, if you're lucky enough to live near a mainline station then it's nearer 20 minutes. My advice would be to look at southfields and the outlying areas near wimbledon, the transport links are better and you're (slightly) less likely to get stabbed by a band of crack addicted, pit-bull toting 15 year olds.