I expect arbitrage will drive the price on the exchanges down quite soon, but there you will always pay a slight premium. (For easy of use and lack of Ether mining fee for the setup of the public key.)
Keep in mind that you can check out EosScan to keep track of the EOS price of all previous and future ICO windows. Make sure you don't pay to much on the exchanges!
RE: EOS Strategy - How to profit off of exchanges adding EOS.