As described it sounds more like MDMA (aka ecstasy or molly, and also part of the amphetamine family); while not harm free it's not nearly as strongly associated with abuse or negative health outcomes as methamphetamine. We have to guess about dose, but I'd say most party drug consumers aim to balance the pleasure of dancing all night with the ability to do so on an ongoing basis.
The article doesn't make clear what dosage the average recreational user is taking.