So.. Like I said, some of the songs would suck to play on guitar hero.. Turns out the Guitar hero versions of the album is better quality than the CD. You just gotta ignore those beeps and blips when you miss a note. One of my original complaints, besides the generic sound of the album was that it was fooking loud. Turns out, The CD is about 10db higher and the compression washed out the dynamic range which means turning the volume up gives a nice, unnerving ROAR. This article
Analysis: Metallica's Death Magnetic Sounds Better in Guitar Hero | Listening Post from Wired.com pretty much explains it. If you own the album, do yourself a favor and download the high quality GH rips and hear the difference. You can actually turn the volume up without being blasted with distorted noise.