Strange - I am 3 months in and not a single cough. Mind you I was 32 years on smokes and no coughing either. Maybe I have a third lung that is full of tar... That said I did have an attack of pleurisy 10 years ago so I can't claim to have lungs of steel
The big thing I have noticed is getting a sense of smell - it has upsides and downsides, the latter especially in public toilets.