What is this song like?
Picture Dave Mustaine (the guy from Megadeth) being asked to write a compilation of Christmas carols, and being asked to not have a crazy solo in it. He got really pissed, punched a hole in a wall, then wrote this song because he is a whore for money.
The whole thing is hammer-on after hammer-on after hammer-on. There are tons of cascades, all of which are very fun, that often slip into some slower sustains, which are still pretty fun. Even during the slower parts of the song, where there are a lot of single note sustains that go on for twenty seconds (if that, this song changes pace constantly), I never felt bored.
However, in the very beginning, there is one very hard part. It is a fast zig-zag pattern that is guaranteed to break an expert's combo and bring an average player down to the red. It only lasts around five seconds, so don't get too discouraged. Dave tried to sneak a crazy solo in, but he was given a quick slap on the hand and returned to the normal pace.
So, in summary: This song is a blast. It constantly changes patterns, and can get you your HOPOcidal maniac achievement in fifty minutes. Buy it if you are a guitarist.