You should probably wear a condom too, just to be extra safe, then.
I've always seen this as a question of risk. What you're asking is the digital equivalent to "Do I really need to wear my seatbelt when driving?"
You can drive around your car two hours a day, every day, without a seatbelt, and be fine for years. You can say you live in a calm neighborhood and say no one ever drives recklessly there. Everyone is still going to tell you to always wear your seatbelt.
You can be very careful about what you torrent. You could possibly torrent lots of things with no problems at all. All it takes is one person at one other endpoint grabbing your IP from one torrent and reporting, to cause a lot of problems.
It's up to you if you want to take that risk, but when you're asking for advice no one is ever going to tell you that you don't need one, and if they are they're probably giving bad advice. There are enough horror stories that many don't think it's worth the risk.
If any of you haven't seen it, this TED Talk by Nina Paley titled Copyright is Brain Damage is worth a look. I can't imagine anyone here that wouldn't appreciate her take.