I prefer the esters of morphine class which is what heroin falls under, closely followed by the semi-synthetic class of opiates, I love dilaudid and oxycodone is alright then finally, just the natural opiate morphine but I always get a morphine rash plus I HATE the pins and needles from IV morphine, semi synthetic opiates don't give me a rash and I just prefer the high of like let's say dilaudid more then morphine any day.