Was easy for me to quit, have some blood circulation issues in my left leg caused by tobacco that may ultimately see it gone( i'm already considering a RH gearshift). Docs words around 7 years ago were simple, "choose, keep smoking you'll lose it!".
I decided on keeping the leg for longer.
If it makes any odds i am also now a big time anti smoking nut. Thanks to them i have the issues with my leg and i'm asthmatic after a near fatal pneumonia attack, hows a temp of 40+deg and breathing pure oxygen for 48Hrs grab you, week in hospital and 12 weeks recovery at home. (pneumonia is fairly common for quiting smokers).
And the worst part, there is no such thing as an ex smoker, you just haven't lit up for a while, no mater how long its been.