In my experiences with heroin, when I was doing street heroin (white stuff cut with lots of quanine), I would feel good, but it was almost a tease. I'd have to do about 4 twenty bags to really get off. I was snorting it however. I'd mostly just get itchy and feel alright, but I always felt like it was a tease more or less.
When I got "raw" which was a thick brown substance that stuck together like it had been rocked, just a bump of it would make me instantly sick. I'd throw up, hallucinate, turn pale, sweat, and feel absolutely fantastic. My vision would change as if everything was far away and coated with glass and I'd have a really hard time keeping my eyes open. I could go all out and snort 10-20mg bumps for hours getting sicker and sicker but never feeling more content in my life.