First I'd check if I was dreaming, then I would probably jump in. Being given a chance to experience a situation like that would be phenomenal, and not taking advantage of it would simply be stupid. Of course at the time I would probably think I could one day go back, or at least some how say goodbye. (Hey maybe I'd get cell service in Equestria) If I couldn't I would probably have tons of regrets. But if I could go back or say goodbye, I would have no regrets in going there.