I went to EDC Vegas in 2012. Its a pretty awesome experience and I'd highly recommend it. If you're a fan of the music you're going to have a good time no matter what, just too many good artist in one place to not find something you dig.
Regardless of the music, the crazy(sexy) costumes, carnival rides, and overall atmosphere are almost worth it for someone who doesn't care for the music. I would recommend either having a high booze budget (if you're into that) or pregaming as far as drinking goes as nothing is cheap inside. At least water is free now though which is clutch for a certain crowd...
Just be sure to pace yourself, I'm not sure about Orlando but in Vegas things kicked off around 9pm and didn't stop until 5 AM...Amateurs need not apply. If you want to know any other specifics I can try to answer.
Next up I want to do Tomorrowland (now in ATL but missed it this year since I snoozed my alarm to buy tickets ) or maybe Ultra (though I'm not a big fan of Miami).
So do a lot of people drink at these festivals or is it mostly a drug induced euphoria that people are under?