It definitely shows that a lot of care and detail went into the animation and art-design of this. Despite using the Madness Style (one of my personal favorites personally), it stands out among most others in technical terms. The only reason I'm not rating it any higher is because of the sound-design for this one.
I don't mind music being played during animations like this. But the song used was terrible, and I felt it detracted significantly from the overall quality of the animation. It was noisy and indecipherable as to what the Hell it was even supposed to be. Personally speaking, I like to be able to hear the sound effects like the gunfire or bullets tearing through concrete.
On a side note, is the Death Metal fan part of the rebels, or part of the army?