There were plenty of arrests due to internet drug vending in the last years. Here is an example article of a buyer from some other online vendor (not SR related):http://ibnlive.in.com/news/consignment-of-narcotic-substances-seized/199434-60-121.html Here is an example of an busted seller (also not SR related):http://arstechnica.com/security/news/2007/11/secure-hushmail-can-still-talk-to-the-feds.arsBut compared to the volume of internet drug sales the risk is still quite small especially for such small amounts like sold on SR. Also vendors using proper security measurements are usually on the safe site.