JH16 is regarded as the creme de la creme of custom buds, but you can get some for as low as 189 bucks! ( http://kozeesolutions.com/product/1/infinity_x1 executive )
Anyways you can use the headroom graph to compare some models: http://www.headphone.com/learning-ce...d-a-graph.php? ( Do not though, that does not compare accoustics, just driver performance )