I thought Metallica's input in the song was ok. Decent riffs, decent lead by Kirk, and the 2 lines that Hetfield sings in it sounds cool, hes got his evil voice again.
The thing isn't really a "song" though. Its from 2 different Tallica unreleased demos that were looped together with drunk rapping over it. I agree in the end it sucks, but I like Metallica's input in it.