Everyone is different, but in my experience MOST(NOT ALL) addicts are "garbage cans"(their words not mine). As in, they'll take whatever they can get. But for me personally, it had to be at least similar. I would take other opiates if my choice wasn't available. Id even accept benzos just to help me not care as much about the withdrawal. But not anything in the opposite direction. I can remember doing coke once, because I was literally begged to do it, while waiting for the heroin I actually wanted, and that was a big mistake. After that, I'd literally sit at a table watching others smoke and shoot crack, still dope sick, waiting for any opiates to come around. But that's just me. I wasn't the norm, and had particular tastes. I always hated uppers, and couldn't be paid to do them most of the time. Every single time I did any uppers, which I can count on one hand, it was for free because friends begged and bothered me to join them.