Ironically, these ERC-20 token sales are driving up the Price of ETH, while those buying the ICOs could have made more money not buying in at all. See the ROI vs ETH on the ERC-20 tokens.

https://icostats.com/vs-eth (be sure to check the ERC-20 filter at the top of the page)


 If the ERC-20 craze continues, you may want to consider the stats in that link. So far, those that simply held ETH instead of investing in most of these ICO's would be better off due to ETH's rise in price.