eBay and Craigslist finds

That depends if the wheel hits a person or not.

Michele Bartoli was involved in a crash in the Tour of Germany in the late 1990s, and a Spinergy wheel hit his knee, causing a massive gash (sharp carbon edges revolving at speed can do that). When he stood up, his femur started to come out of the gash.

The wheels were banned by the UCI shortly afterwards.

saw a guy riding them on an outdoor velodrome here, wasnt sure if I should say anything to him