I'll be honest: this game won't do much good for absolute beginners. While it has various learning videos and explanations, it is more of a game meade for practicing guitar, not learning it from ground up.
If you won't expect that this game will teach you how to play, you'll be satisfied. It's good at what it does: practice. Many guitararcades minigames to practice one technique or another. Technique challenges to master your skills even more. And the best part: the songs. Playing guitar parts of your favourite songs with quality accomponement just feels awesome.
P.S. You don't need Ubisoft real tone cable to play the game. Just your guitar and no-cable fix (google it up)