Jun Ishikawa is... amazing, really. Zero-Two has got to be one of my favourite game themes of all time (by a long shot), and each and every facet of this (IMO underrated) game's music makes me so... cheery! The only problem is that it, for some reason, does not include the Miracle Matter fight music (the riff off the standard boss theme).
I give it a 9, because it's missing Miracle Matter (a song I crave surprisingly often), and because its instrumentation is limited due to its age. Other than that, it's fantastic!
LISTEN TO ZERO-TWO. Your life will be altered for the better, I swear it. (The number of times I've doodled him in the margins of my chemistry notebook I do not care to count...)