If you use 2nd class or lower media, then if you do get a "good" disc then it will work just as well as a TY or Verb, the problem is the percentage of coaster material gets higher as you go down the list.
Out of a 100 spindle of garbage media you'll still probably get 3-5 perfectly working burns, but they will deteriorate over time.
With GH being a particularly high demand game (the laser is constantly reading the disc during note scrolling), good quality can be even more important than usual.
and -R's and +R's both work.
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Wiazards Of Gore!!! Wizards Of Gore!!!