Heh, I like the synthed version, but I also like the original version. :p Perhaps I could use both - when you fight Iosa (boss 4), you fight her in two stages. In the first, she's in a 'mech shell, but in the second part you fight her "
real" self, where she's unarmed, but still as dangerous. There could be a little delay when you destroy her mech, where she gets miffed and says something (like a taunt about how you're dead meat), and the synthed version of the song begins to play.
Sound good? Or not?
As for track name, if it's going to be used for Iosa, how about... "cat fight"?

Or maybe "One Girl Army".