Thanks to Gamesack, I just tried the Streets of Rage triple pack demo on Xbox 360. Man, these games are all awesome, so I bought the full download. Even part 1 plays so fine and has such a nice music, that I don't care about the rather simplistic graphics compared to part 2 and 3. And I'm a graphics whore when it comes to 16 bit games. I can't wait to play them in multiplayer with my girlfriend.
It's so cool that the triple pack includes all US, JP and EU region versions.