I rarely ever like covers at all but I have heard a couple lately that I like a lot. Powerslave by Anaal Nathrakh and Remember Tomorrow by Uncle Acid & the Deadbeats. I am a big fan of both of these bands but you may need to appreciate them already to like their versions. They make the songs sound like themselves which I think is a necessity if you are going to record a proper cover song. I also like that version of The Number of the Beast that is at the beginning of that movie 'Spun'