Seems, It is only getting better. Lumia 520 has climbed to 3rd top seller rank behind two other Nokia phones at Amazon China. The top two ranks have been claimed by dirt cheap volume device Nokia 1050 and this may hint about kind of volume Lumia 520 may be dealing in at the moment.
Lumia 520 is currently doing very well in terms of sales nearly everywhere and China seems no exception. At Amazon China, lumia 520 is top selling WCDMA phone which means it is top seller China Unicom phone. Lumia 520 actually holds 1st, 3rd and 5th ranks on this bestseller list. Not only this, it is 5th overall bestseller phone at Amazon, which certainly means volume as devices like Nokia 1050 are ahead of this on top seller list.
Thanks Roger for the Tip. Cheers!!