I've considered transition for a long time. I've given up on it, now, for social and financial reasons, but I think if I'd been more open about my gender issues when I was younger, things might've been different. Then again, money would still have been an issue.
But yeah, in the hypothetical magic scenario, I'd love being able to switch from male to female at will. Hell, I'm pretty sure I'd take the offer of a single-time switch as well.