How to choose the type of hair extension?

Has been widely accepted by the market today trace hair , then type trace how the hair is conducted to select it ? Mainly in the following three points:
    1.Mechanism trace class hair hair is very dense, hair piece is thicker than gluing to the class, if it is , then the whole head of hair about four laps to use this type of trace hair ventilation is very excellent, the only different is the hair above have sewing line , if not , then on the type and hand-woven almost, currently used in this way is a monolithic Europe to take art , indeed, basically feeling less , the price is not expensive nor cheap, compare quality and prices for fancy than the crowd.
    2.Gluing class trace hair because the hair piece is not very thick , so it was very touch and comfortable, but the whole head of hair is conducted , but also need to better results when about to about 55 , there are many film above the head , even when a great feel touch , but not good ventilation for people who want to feel slim is preferably chosen in such a way hair .
    3.Hand-woven hair trace class must be the most comfortable and the most outstanding stealth effect , because the appearance can not see the sticky glue , can only see the hair, but the price is more and more , people are more concerned about fat butt most preferably selected in this way .
Do you have a further knowledge of hair extension?