Last year in early december I bought eBitcoin token which turned out to be a scam. Luckily for me I sold them before the ePRX snapshot but alot others have made losses. I really believed this token would be a succes but I've realized that alot of these ERC20 tokens have the same things in common. The devs (or better said scammers) create alot of hype and pretend their token to be the real deal while they never intended to create a working product. I've thought about investing in tokens like Credits and Elixir but I'm afraid they are all the same kind of scam.
Do you trust them?
Credits are really a very good project. The way to check for good ICO projects is very easy. You can check out Twitter or Medium for posts and their community. If it is a potential project, many interesting things will be public on those social networking sites and it will interest you.