Not much can be said other than Amazing. It's prefectly composed with added sounds from the game itself. The only somewhat bad part is that the drumming get's a bit frantic, mostly because it's the only part that wasn't actually performed. If you've listened to it 10 times, and still can't get the lyrics, Nintendometal.com has the lyrics for all thier songs.
The second to last level has 3 random songs when you start it; this is one of them. Also, as constantly as I download NES remixes, I'd easily have to put this in the top 10. It'd be better if there weren't so many MegaMan 2 ones, but that's BubbleMan for ya.