http://muertexnghvyoa2wpel3xxwzdoz5ayzo3gsdczvhucqe6uznconlsuid.onion/article.html?article=14
We recommend using XMR over any other currency, hence why it is the default option due to its built in security, and the fact it is near impossible to track transactions made with it. You may still make contracts using bitcoin until the end of this year, after all support will be permanently pulled. We will be posting another announcement 5 days before this happens as a reminder of this fact.