Glue in hair extensions?

My hair is quite thin and short, and I can never have it too long because it just goes all fluffy and horrible! I really want long thick-ish hair and would like to see about hair extensions, but ones that will give me the less irritation and pain! My friend got some plaited in and she wouldn't stop complaining about them itching. I would go to the hairdressers to have them done, what do you think of them?