One thing I like more about SL than I like about RL is that it's so much easier to change your style and looks there. I'm constantly switching from Ballroom fancy clothes to jeans and t-shirt or cool black leather clothes, and hair colour and style takes only a click to change.
Unlike in real life, where you're sat in the bathroom for an hour putting product on, waiting, rinsing it off, cleaning the bathtub, etc, and then you're never quite certain of the outcome. For example, the chocolate brown I wanted looks rather black on my hair. Oh well, it'll be gone in 30 washes anyway.