It's been a while since I saw this, can't really remember the ending. I do remember that, as many have already mentioned, the superpower shit fagged this anime up. It went from "OHSHIT WE'RE MOTHERFUCKING MAFIA GODDAMNIT I'MA SHOOT YOU, BAM DEAD MOTHERFUCKERS" to "hi lol i'm a your average mafiaguy nothing to see he- WHAT THE FUCK I'M A GODDAMN HELI-FUCKING COPTER".(or something like that, as mentioned earlier, my memory isn't very clear)
Ah well, even though the second half was shit compared to the first one, it's still awesome compared to most of the stuff that's out there.