Pinkie, I don't think your description of E is inconsistent with everything that's been said here... The seratonin rush makes you feel happy and loving. Your environment will affect how you express that, doing E at a rave is completey different than doing it at home, for example. E used to be so novel that I thought it was great anywhere, but later I would only do it under circumstances that I knew would enhance the experience, because it's such a significant factor.
I do agree that it's often 'enhanced' with crank/crystal meth which is what really makes people clench their teeth a lot and be up for 24 hrs or so. Probably not opiates though, because they're expensive... DXM is apparently popular because it's cheap and legal and will mess you up a bit.
Personally, I like to be a bit speedy when I do it, but prefer 'lighter' stimulants with purer MDMA. And I've had the real stuff, in many countries including the Netherlands. I've also had a lot of stuff that was passed off as E, but that's one of the risks you take with an illegal drug.
There used to be a harm-reduction site in the US that sold testing kits... can't remember the url, it's been a while now.
edit: found the site, a lot of good info here:
www.dancesafe.org
Crisp