Pros:
Not a neurotoxin.
Easy on your body.
Pleasures you in a unique way that feels great.
Cons:
Makes you constipated.
Difficult to piss while on it.
Very addictive.
I've had heroin a few times (snorted) and I don't ever plan to have it again. In my opinion, heroin isn't a "fun" drug. It just pleasures you...it gives you a beautiful feeling of warmth throughout your body and clouds your mind, stopping you from feeling any pain. It's like nothing could ever make you sad, there's no fear or anxiety or anything. You slip into this opiate-haze (nodding) where you're not unconcious and not completely concious...it's almost as though you couldn't be bothered being concious anymore.
But that's just it...there's no anything. Heroin pleasures you but it's not fun in the way other drugs are. Weed is fun and pills are fun but heroin just pleasures you. It's impossible to feel bad on it, but you don't feel truly good either.
I think whether or not you like heroin depends on what you're looking for out of drugs. I'm looking for something that is lots of fun...something that afterwards I can think 'yeah I had a good time on that', and I get that even when I just smoke weed alone and download stupid crap off the internet. I get that after a night on pills, and so on. But heroin doesn't leave me with that feeling.
That said, heaps of people love it to the point of turning it into a lifestyle, so you might like it as well.
Oh and yeah, it is as addictive as people say. You will feel it after one use. You will find yourself trying to convince yourself to do more. It will sneak into your thoughts without you realising, or it will beat your other thoughts down and replace it with "Smack: It's so tops! Let's do some!" I don't feel that I have the maturity or drug experience to use smack with any sort of regularity and keep it recreational, and so I'm staying away from it.
Oh and ps, the fact that a drug makes you vomit has nothing to do with how good it is for you...I often vomit from pills, seeds with LSA in them frequently make you vomit, and so on. This is just something that people who have never had smack and have an unreasoning fear of it will bring up to rubbish people who use it.