This site has a very high probability of being a scam. Why would anyone take a 50-50 bet when the risks of it not actually being 50-50 are quite high? It wouldn't be very hard for the owner to do the following:
- Owner has a reasonable amount of BTC stashed away. When owner identifies the side where new bets are coming in, then he puts a large amount of BTC on other side to essentially swindle them of their coins.

Also the design of the web site is atrocious.

Nice try, but in all honesty very likely to be a scam. Stay away. You want a 50-50 bet? Just play dice!