I'm no musician; I just love listening to great music. Bass parts for me were always very important as the underpinning of songs. JMX has always performed this role extremely well, eg. Hell's Kitchen, but can stretch out into more demanding parts when neccessary. This is the main point. JMX has more feeling for a song, besides being more proficient. 'Arry is also a terrific player, and has moulded his style into Maiden's sound (and/or vice versa), but that also is the point. His playing is generally of a particular style. Still great, but more limited. JMX got my vote, but I love Steve's passion.