I only drink decaf, and the whole deal that decaf is horrible is BS. There's good coffee, bad coffee, good decaf, bad decaf. I can't live without coffee so I'm willing to spend the extra $$ and buy the good stuff.
The only drawback I can think of is feeling drowsy in the morning for a couple weeks, and if I want to avoid that I sometimes have a normal coffee in the morning after a full breakfast (my only coffee throughout the day). I've almost ruined my stomach having coffee for breakfast every day for years : (
See coffee is not only a stimulant, but pretty acidic. Not a great thing to put in your stomach after >10 hours of it being empty.
Pros are so many though, you don't realise how antsy caffeine makes you until you cut it off. Less headaches, slower heartbeat, less heartburn and indigestion, among others.