I have read many of the FREE TRIALS ads, and if you look hard enough, you find catch loops. I am to the point I don't like to use my card for anything, until I have done business with them, so I
buy a (name credit co.) money card at a store or bank, and make my first purchase on it. If they turn out to be a scammer, just drain the card and toss it. After you learn them and develop a trust with them, you can put them over onto your permanent card.
Thanks for watching out for scams. Be sure to post them at sites like that one girl's list that jumps on that one boy's list for it's sloppiness.