I'm not saying KCS is shitty or anything, quite the opposite I've actually regretted not investing in it before and the platform is awesome.
I like the COSS project even more though, I like the Crypto One Stop Solution it represents, being a well rounded platform (ICO + FIAT) while always giving 50% of trading fees.
I don't think they are that much competitors, there is space for both, COSS being a bit "riskier" but also now being the one of the two where there is the most to gain from.
This is possible when COSS is getting better and better, now you can see that the trading volume of the COSS trading platform is rising sharply, which is really a good sign for a given page new translation.