I quit caffeine cold-turkey around March, because I was drinking too much (effects of tolerance?) and feeling jittery throughout the day, as well as having trouble sleeping at night. Slight headaches subsided after a couple of days.

Now I don't necessarily feel like I have more energy overall, but it is a lot easier to get out of bed in the morning and I feel like my energy levels are a lot flatter and more balanced throughout the day.

Still love the taste of coffee though - decaf soy latte is part of my normal breakfast routine.