My experience was this: I quit smoking, then started again with spliffs. I got some gas station ecigs then bought a real one. Was cool except that I used it a lot, alot alot. I went through one of the gas station blu cigs in about 5 hours once. Then I bought my own and used it a lot until I ran out of atomizers and the old atomizers plus the shit smoke that I bought led me not to reup. I smoked cigs for awhile again then quit tobacco altogether. I've had spliffs here and there and if I hang out with friends its pretty much a given. What sucks is that the addictive nature never leaves. I'll have no tolerance for weed, but still smoke 3 spliffs or so on a night out.
I still think about tobacco and I don't hang out with people. Day to day, I'm fine, but something is missing. At my worst I've considered buying a pipe/cigar/ecig stuff. I almost smoked a chamomile cigarette, but never did. I live at home so now that I don't smoke it would be hard to smoke a chamomile cig or a bowl or tobacco pipe or whatever.
Wish I never started, but now that I've stopped I'm no better or worse off. What sucks is that I'm approaching a year since 'quitting' not counting a few slips and I'm no better off mentally. New years parties are still going to suck with no tobacco. And it's been a damn year, I'm totally used to not having it, but with other people I like to get away hang out and puff.
Fucking wish so bad I never started. Seeing unhealthy old smokers helps a bit, but doesn't help the right now the 'I'll quit later' mentality.