No one gets arrested for downloaded music. Just massive fines... massive.
This server isn't really 'secure', your IP(among other identifiable data) is definitely logged. This site is ran out of USA, and subject to California law(pretty sure it's hosted out of Cali), Federal law(the real bitch), and international law. Which means warrants(federal or state) are definite possibilities, and your identity could be a 'click' away for law enforcement.
Most US ISPs will cooperate without a warrant.
Just remember, everything you post is indexed on every major search engine. Don't put the pieces together for anyone, and you'll probably be safe.
You don't grow weed. You grow plants. You don't smoke marijuana, you just smoke. Etc.
It's really fucking naive to think cops don't visit this site.