the project chose for the eos platform. it is a choice for the strong, as its difficult to build something on eos yet. but why did you make 2 tokens? its better to do it alone but fully
the price of the first token (POW) depends only on the trading volumes of it. It growes up with every buying abd fall down with every sell, But price for second token (POWx) related to external exchanges from one side, and fixed with the POW 1 to 100 ratio.
this gives you opportunity to additional speculation (you can buy POWx cheaper on external exchanges, and change it to POW, or sell expencive etc)