Google enabled Navigation for Hong Kong
I tried it out today, going from wanchai north->wht->ssp->po kong park->eht->cwb->mid-levels. I purposely deviated from the calculated route and seems that the routing from Google Navigation is quite good! And voice directions are very clear! Only tried in english but cantonese navigation should work, too!
But sorry, on Android devices only. If you have iDevices.... Good luck with your apple map