I was really big into them for a while, but they came under a LOT of fire for ripping folks off, from using artwork without permission for their album cover and shirts, to downright stealing music. That's bad enough but worse is that when confronted on it, they've been complete dicks about it.

It doesn't change how good the music is, but it was really disappointing to hear about, especially how crass they were about the whole thing...insulting the artist they ripped off for their shirts and album cover, and claiming they had never even heard of the chip-tunes music scene when the person they copied the most from is a huge proponent of chip-tunes.

http://www.wiretotheear.com/2008/05/13/crystal-castles-caught-ripping-other-artists-off/

http://gamemusic4all.blogspot.com/2008/05/crystal-castles-caught-stealing-music.html