It's not safe to buy Aion gold, most gold selling sites will somehow put a keylogger on your computer and get your login/password. It happened to my friend twice and he raged quit after the second time.
another bad thing is, when you buy aion gold, they send it to you via the mail system. anything over a certain ammount of kinah in the mail system gets flagged and they check it out. I had 4 friends get banned for this. 3 bought kinah and the the 4th was actually one of my friends sending another a shit load because he was quiting aion. the last one was a legit trade and not gold buying and they still wouldn't give his account back.