As you may know EOS ICO has just went public and they are releasing the first 200 million coins to investors after 5 days. Then every day after they are opening up a 23 hour period to invest in 2 million coins that will be shared according to what percentage of ETH you have given them.
There is already nearly 50,000 Ethereum that was invested into this smart contract ICO. So the hype is making the amount of coins you will receive possibly much less than waiting 10,20,100.... days into this. The ICO is projected to give out 2 million coins for 341 days. So you may get more EOS for your Ethereum if you wait. Also we have no idea of the longevity of this ICO and if it will live up to the hype.
After I invested some ETH into it I was going to recieve around 2,700 EOS tokens but already I am down to 2,100 which has only been 2 hours into the ICO meaning there is over 4 days and 21 hours left. Once the hype dies down people may make get a lot more tokens for their ETH if they are patient. Also this ICO could be worth nothing in the future.
As always, only invest what you can afford to lose.