Best to avoid sites like that, pretty sure that 90%+ are scams. The more popular coins become the bigger the amount of people who want to take advantage of the hype. The best way to get the coins you want is to use an exchange or service that has good reputation and a solid track record (it does not make it 100% safe but it is very very close to it). Just go by the idea that if it sounds too good to be true it most likely is
Well ShapeShift.io seems very good to me. Instant exchanges and most of the cryptocurrencies are included in the list. Very less fee. But anyways, from now on I will do much more research before sending my BTC to anyone. As recently, I've been scammed here as well in exchanges two times... making an amount of 0.22 BTC overall.