Just this week, I decided to quit cold turkey, and drink nothing but water, and it has been eye opening. I didn't realize how much I depended on the drinks to get me through the day. But going just-water is definitely the only way I could have done this. Something about knowing I have nothing to look forward to besides water helps me just drink water, instead of waiting until I can find some energy drinks, and getting dehydrated in the process.
Not everyone is going to have as unhealthy relationship with caffeine as me, but I'm hoping my kidneys and gut will thank me. I know 22 year olds seldom suffer from heart attacks, but I'm not going to be 22 forever, so might as well start now.