definetely true, I've noticed a slight difference between Generic MPH pills I occasionally shoot (dont hit as well) and Biphentin which is what I'm scripted and prefer to shoot as it dissolves faster hits harder and is less messy.,..so much filler in the generics i have to filter like 2-3 times for it to be clear enough for my liking
edit: To be clear, shooting coke is definetely better and a way more intense and unique experience than shooting MPH. Shooting ritalin is like shooting stepped on coke and there isn't a bellringer. Just a feeling of stimulation, a slight "rush" (more akin to a nicotine buzz with more stimulation tbh) and a similar feeling of tightness/head buzz to that of IV cocaine.
Works for me tho and I like it, also feel like it ruins my veins slower than cocaine (atleast Biphentin, the generics have so much filler i'm sure i never get all of it out)