First of all, I've only seen three episodes, and I don't know anything about anime adaptations of manga, but this series seems to be delivering on a very ambitious set of goals. It's a Japanese morality play infused with huge amounts of young female hormones, often with S&M overtones, all wrapped up by a great score and eye-popping visuals. It's getting right at what I assume to be the fundamentals of manga; a high-octane blending of very adolescent and very adult themes.
I can't tell exactly who this show's intended audience is, but I'm a 63-year-old American gaijin dude who's played guitar and drums for 50 years, and I find myself laughing out loud at how much fun these girls are having rocking it out. The sexual themes presented do seem to a non-Japanese viewer to be a bit uncomfortable, but maybe that's just my uptight American perspective. At least the sex stuff seems to be offered with a bit of a wink, as if to say, "Hey, we get this is weird, but it's also kind of fun, right?" After all, the young female characters are all from very rich and repressive families, and they're bound to have lots of pent-up tensions, which would include their libidos, as well.
Finally, I loved the Red Hot Chili Peppers reference because, when I was in college at Michigan State in the 80s, I used to hang out with Brad Smith's band The Generics, and sometimes Brad's little brother Chad would sit in and play the drums after band practice. Man, if only I had taken some video of those jam sessions ...