Questions about buying kundan and polki jewellery

Hi
I have never been much of a jewellery person but lately seeing others I feel tempted.I don't know how to judge the quality of kundan sets I see on the stores.
They are not real gold or diamond but atleast I want to know which ones will not break after one time wear.
How do you judge those?
They are all in the Indian stores in Los Angeles area and range from 20$ to 300$.
what about the ones online like in ebay?How do you judge which ones are good or not?