It doesn't give me the jitters either like drip coffee, I hear there is less caffeine in espressoDarker roast coffee (as a rule) have less caffiene than the lighter or less roasted coffee.
http://www.coffeedetective.com/how-much-caffeine-in-coffee.html
Darker roasts do have less caffeine, but espresso doesn't have anything to do with which roast it is; it has to do with being more concentrated. By volume, espresso has more caffeine than regular coffee.
Back to the topic: I like coffee for two reasons: I love the smell and flavor, and it offers a very harmless and even beneficial daily stimulant. Coffee got a bad rap back in (I think) the 70s or 80s when there was some dumb study that correlated coffee consumption with cancer. The study was later retracted (it wasn't done right) and numerous subsequent studies have shown that it can have many health benefits. But ever since then, people view coffee as a guilty pleasure, when in reality, it is simply awesome, being both an awesome beverage and an awesome drug with few harmfull effects besides jitteriness and slightly stained teeth. For me, I limit my coffee intake to one cup a day. More than that and I get too nervous-so one cup is my sweet spot, although I usually have two on the weekends.