This was a fun, polished, little game. I really would give it a 3.5/5 or perhaps a bit lower, but figured I'd round up rather than down. It's composed of some rather easy puzzles (except one; see below) but most of the enjoyment came from exploring the narrator's little world(s).
There weren't any technical bugs that I came across except that it's possible to get to the end-game without actually haven't accomplished what the end-game says you've accomplished. (Spoiler - click to show)Namely, I ignored the mind-control device in favor of breaking into my evil twin's lair... I ended up in a jail cell, only able to guess at what I'd done to get there! It's worth the time it takes to play, though it's not likely to have a huge effect on you. Fun, but not difficult or deep.
If you're not super-knowlegable about the band (or you are but you're not much of a mind-reader) and you get stuck (Spoiler - click to show)at your evil twin's bookshelf, you might need to go here.