Ketamike
If anything, taking opiates should produce more euphoria dose for dose if you're ill, as in just about every study I've seen, the use of opiates in the absence of pain is more likely to produce dysphoria (I know that doesn't quite square with the fact that people who use opiates for pain relief are less likely to become dependant).
Methinks the person isn't being quite truthful (a dealer not telling the truth, shock horror!). Sounds like typical "this gear is really excellent" dealer hyperbole; when was the last time you heard one say, well it's not up to much, but it was cheap and there was nothing else going? Not too often.
Best off just trying to get in contact with the reliable people you know