I played both on location last week and as I'm terrible at pinball I can't really speak to the code -- but as far as the shots/layout go Iron Maiden is something special. It really stood out above every machine I played that day. In fairness to BM66, it was one of the more enjoyable shooting machines for me as well so it's not really Iron maiden vs BM66, it's Iron Maiden vs every other pin at this point. It has so many satisfying shots and multi-balls right from the get go.