As mentioned earlier .... BUYER BEWARE .... you have to check several things before hitting that buy now button. Ratings, reviews, is it in Thailand , is it official store ....
and be wary if the seller chat tries the ' oh sorry that's out of stock but I can get another in a few days'
To be honest, it can be a hit & miss most of the time, it's just that one time you end up getting taken.