They do have an interesting sound but it is true that they can't play their own material. The proof that their albums are made by splicing notes together is all over youtube - there are some cringeworthy vids of them playing one of those 'bet you can't play this' licks. I don't like the sound personally but I do admit the music is pretty progressive but what you hear is no reflection on their real abilities as players (whether that makes a difference to you or not).