Last year I attempted to ask out a girl (somewhere between 18 and 20) that I thought was hot. Normally I wouldn't go for anyone that young, but she's hot and I felt I had an "in" in that she saw my band play at a concert and proceeded to like our facebook page. She turned me down, and seeing a lot of her facebook posts over the course of almost a year later, I dodged a HUGE fucking bullet. I'll probably try to avoid that age range from now on, if I can help it. But someone as 5ever alone as me, it's hard to be picky with age, as long as she's legal, available, and good looking.
Now don't take this as me being like Zeni, I have a coworker that's 5 years older than me I would want to ask out, but she's not available.