Not bad, not bad at all
Personally, Flying Battery is one of my favorite themes of the older games. And I'm proud to say that you do it great justice.
I really like the lighter tone that you put it to, as well as the techno style along with it. It loops nearly perfectly, but it just sounds a bit odd going from such a heavy beat, back to the low-paced opening. Maybe that's just my personal preference, but al in all, it sounds great. 9/10