I would say that the most important is to stay cautious, there are a lot of scams in the cryptocurrency world, that's for sure. Remember to check twice every website which you want to use to buy cryptocurrencies (and do some more). Check out for example what CoinDeal's COO and Coinfirm's Co Founder speak about scams in the cryptocurrency market:
https://www.youtube.com/watch?v=83JnxuUUJ5oIn addition to that, we have to check their reviews for this is a way we could put any conclusion. I know some sites have paid reviews to promote their sites and that's gonna be hard to find out. Trading is risky as we know that, it is up to us either to put trust in a certain site or just follow what the others mostly been used. It is not about holding you to try with the others but we also have to be practical unless you don't mind losing your money.