Old bikies used to manufacture the shit from phenylacetone, got pleasant speed from that shit, read about the old timers during the 70's manufacturing amphetamine, it was apparently an intense rush, all the time, whichever way it was ingested, but then 1980 when the crackdown on MDMA and phenylacetone, bikies looked to more methods, such as abducting skilled chemists and telling them how to make their speed, hence the introduction of ephedrine/pseudoephedrine based speed, which makes d-methamphetamine, which lead to junkies being on the shit for 5 days and then crashing, yet in the old days of the 60's/70's when P2P-based amphetamine was around, people could stay up for 11 days straight and not be violent or aggressive or any of the bullshit that we see today with d-methamphetamine.