Going in person allows you to closly examine the jewelry you are looking at. YOu want to know what the carat is(percent of gold to other metals). 24 carat is pure and too soft. 12 carat is standard. What you will want to see is fine detail in the gold and in the clasp. Cheap clasps are bad jewelry.
I have purchased several gold rings from southeast Asia and have found their quality to be very good. I would advise asking a jewelry professional on their opinion as well.
My experience was not good purchasing jewelry from different parts of China. It looked good, and was marked properly. But when I had it tested, it proved to be just really good fake.