I actually signed up for both this Friday... As soon as they let us in for Boo Bash, we are going to take the backstage path next to Tony's to get to Tomorrowland Terrace - hopefully get checked in by 7:15 p.m. - enjoy a few treats and then head to garden area for fireworks about 7:45 p.m. (our goal is really the reserved view since we won't have park tickets that day to stake out a spot way early... plus enjoy a few happy treats.. I'm looking at you chocolate covered strawberries and POG juice...). I've seen photos of the reserved area to know it is still full of people, but not a wall of people like the regular viewing area (and those folks have to be there to get their spots 60-90 minutes in advance, I've heard).