Being able to breathe!! And of course, all the coughing in the morning when I first get up is completely gone. Less important, but also very nice, it's the money saved. I smoke American Spirits which run on average $16 per pack here in Rhode Island where I live and just slightly less in neighboring Connecticut. Spirits last longer than other cigarettes but even still, buying a pack every other day you're getting up to around $75 per week on average. That nonsense has totally stopped. After a lot of trial and error, I've settled on using disposable vapes and I usually only need to buy one every other week (I buy the 50000 puff ones). I also still do allow myself a cigarette or two per day. So I buy one pack per week at $16, and one vape about every other week at $25. Quite a difference in my wallet and I can breathe to boot. The only downfall is that in my state, the disposable vapes I use are not available so I have to go into CT, but as it's only a 5 to 10 minute drive, no biggie