It took around three weeks, but you could get it done slighty faster.
I shipped it to my brother via Fedex International Priority (3 days), he then sent it to the nearest Chinese embassy in my home state (2 days). It then took around 6 days until it was returned to my U.S. home address with the visa. My brother then shipped it back to Korea via Fedex 3 days later and it was in my possession 4 days after that.
Total = 18 days
I would recommend to give yourself at least three weeks in case there is a problem. My friend completed his application form incorrectly and that added an extra week to his turnaround time.
If you are a U.S citizen look at http://mychinavisa.com/
My father has used this company many times for acquiring Chinese visas for business trips while he has been abroad.
They are the go to visa agency for people acquiring visas from their home country while they are living abroad.
The only downside to this method of acquiring a Chinese visa is the cost (http://mychinavisa.com/rates.php
The good thing about their service is that you can ship directly to them and they will ship you passport back to you via Fedex International Priority ($65).
(Total Cost = Consular fees + Service fees + FedEx return shipping fees)
US passport holders $140 per visa
Standard Service (4-6 day processing) $43 per visa
FedEx International Priority $65 per order
You are looking at a minimum of $248 (non-expediated visa processing) + the cost of shipping your passport back home from Korea. I think if you were to use mychinavisa and there were no unforseen delays you could have you passport back within two weeks.
Hope this helps.