From my experience (but I could be wrong), pimples grown on dry skin takes a bloody long time to go away. And by that time, the scar comes and stays for a long time. 
As a result, when I have breakouts, I always wish they would be on my t-zones because they disappear faster. 
I am nursing one on my cheek now. It was there for a couple of weeks (I made the mistake of leaving there for too long) and then I did exfoliating peels, hydrating masks followed by Neutrogena's BHA peel (can't remember the exact name off hand) on alternate days. It did dry up the pimple and now it's half gone. It used to be really big and liver-red. 
As I said, only half the battle won. Now the scar, argh.