I was smoking for many years. I used to hang around with kids a lot older than me. They hit the age where drinking, smoking and drugs became decisions and simply put, I was younger and easily influenced. I became addicted to smoking through peer pressure, and found it extremely difficult to quit.
In more recent years, I've bought several electronic cigarettes. It became a bit of a hobbie, buying the latest models, mixing up different flavors and strengths of liquid, but I was still smoking cigarettes on the side (less than before). My brother has been on solely the e-cig for about 3 years now, but it just didn't have that 'dirty' feel of a cigarette.
Anyway, I really wanted to quit smoking, so I decided to stop. I considered myself a drug addict, and that in order to quit, you don't give yourself little bit of the drug. The key was knowing how the addiction worked (or at least convincing yourself of how you think it works). My scientific explanation (right or wrong I do not know) is that your body requires a certain level of nicotine in your blood to be 'satisfied' and while you're not at that level, you will suffer from nicotine withdrawal. This withdrawal will only occur while there is still some nicotine in your body, but once the nicotine has left (after 72 hours), you will no longer suffer from nicotine withdrawal, but from associations with smoking (basically, the habit rather than the addiction).
So I quit. For 72 hours. 72 hours of HELL! I nearly killed a guy for driving the wrong way around a McDonalds car park. Because of my understanding of addiction, I couldn't allow myself to have even a single pull on a cigarette, because that would put a tiny bit of nicotine in my blood, which would take 72 hours to leave, and so I'd suffer from withdrawal for 72 hours from that point. Simply put... I never took another puff. After 72 hours, things got remarkably easier. I had queue induced cravings, after eating, while walking, after waking up, but these were because they had been part of my routine for a long time. They get weaker and weaker, and now I'm probably down to one or two queue induced cravings a month.
I quit smoking on the 4th of January this year (I don't like doing new years resolutions as you should do something because you want to do it, not because of a specific day). To some, that may not seem like long, but I'm sure to a regular smoker, or anyone who has quit before, that is pretty impressive. I'm not going back to smoking, I haven't had _ANY_ nicotine since I threw away all my stuff for the fear of having to go through those 72 hours of hell again, and being too weak to do it. Maybe someday I will enjoy a nice victory cigar with my friends, but for now, it's simply not going to happen.
As for the feeling. I do feel a lot better. I was always reasonably healthy despite the smoking, and I haven't noticed too much on that side of things. I feel great though, simply because I wanted to quit for so long, and it really gets you down when you're unable to quit, and you feel weak, depressed and controlled by little white sticks of smoke. I taste things a lot better now, I smell things a LOT better. Breathing is a little bit easier, I don't have a permanent cough (was only a small one). The most surprising thing for me, is how less stressed I feel. I thought I'd get stressed at things really easily and have no 'cure' for it, whereas before I'd just have a smoke. At the moment though, I'm simply not getting stressed half as much as I did while I was a smoker.
Anyway, sorry for the essay, but I figured if someone wanted to quit, it might be useful for them to hear. I had tried some nicotine replacement stuff before, but I realised I needed to get off the addiction, and by my own theory, having a patch or gum would simply attempt to address the habit of smoking (which took months to truly break) but it would keep the addiction. I think it's better to fight off the addiction first... and it worked!