Spamcop is hardcore. In 2011 they blocked email originating from T-Online (Deutsche Telekom) for several weeks.
Spamhaus initially also blocked T-Online, but relented after a few days under pressure from Deutsche Telekom.
We got in hot water for that, as we were blocking incoming spam using a Spamcop RBL, and T-Online is probably the largest single email provider in Germany.
I researched the issue, and apparently the problem was that T-Online had EOL'd its dedicated server hosting business, and there were a lot of unmaintained, disused root servers sitting around. Many had been hacked, and were being used to send spam. In its infinite wisdom, Deutsche Telekom had set up the root servers to relay their outbound email, by default, through the same mail servers that were sending the email for millions of T-Online managed hosting and dialup customers.
This was not a good idea.
So, while it was inconvenient, I can't fault Spamcop, and in fact I applaud them for their hardline approach. Just be warned.