This interview with a former recruiter and who now disavows the whole movement is quite interesting and illuminating: http://www.npr.org/2013/10/25/195238189/how-does-an-islamist...
His time spent in an Egyptian jail in the company of other Islamists changed his mind about the ideology and its aims.
Goes into detail here too: http://www.npr.org/player/v2/mediaPlayer.html?action=1&t=1&i...