How is it sadistic? Like you said they're bloody wankers, they deserved it. No point in feeling guilty about it, they're a bunch of morons keeping you from your sleep.
when i called, the operator at DPS first suggested that i talked to them. i was silent for a moment, because i thought to myself, "don't you think i would've tried that already?" the last time i complained to our resident advisor, you wouldn't believe what he told me: then i told her "i did, but they went quiet for a little while, and now they're back up at full blast again." she immediately asked "would you like me to send an officer there?" "yes please. two if you can. it's a big crowd." by 5 am i was able to go to bed.
Nobody would have seen you doing that at that hour of the night of course, but still I'd stay what you did (Calling the cops) was the ultimate solution, and its great that those freaks got in big trouble, finally. IT