I used to buy from taobao via the usual suspects, first TaobaoFOCUS and then TaobaoRing. They were OK, but now I have found tsui-store.
Communication goes per e-mail (service@...). They answer all questions and requests. They reply promptly.
Packaging is good, but they do not add unnecessary packaging material to make more profit on the shipping costs.
My last order was made on a Saturday, they bought the cake on Sunday, and because it was the last cake they bought it before I even made the first payment. They got the cake on Monday and shipped it the same day.