I did. First mage, then ele at 2k in MoP. You're quite right; a mage has more control and is more mobile. However, mages are also harder to play well and have more responsibilities in arena. Ultimately, I would probably choose to play my mage instead of my ele, if not for my boredom of mages after having played the class for years.
I'm currently leveling a shaman since I've already gotten bored of my mage. I mean, who doesn't want to shoot out gigantic meatballs critting for 80k+ with a 50% chance of proccing another meatball for 40k, back to back?