go2arena site legit?

You can make your own conclusions

Some people had problems because the keys where stolen or bought with false credit cards.
Or some people bought the game and they told that they can't give it because of security problems, others didn't get nothing. Buy on your risk

DLCompare.com lists gameprices from websites that most often can be trusted (i've worked with dlcompare on a tournament in the past and they do their research)