I can't speak for every coach, but if you have 7 ten-packs and are about to get 10 more ten-packs when you arrive, I wouldn't worry about using character builders quite yet. There would be too much in flux in your character builds the moment you get your 10 packs.
If your group has pre-selected classes, and arrives early (up to 30 minutes), you will be well ahead of the curve!
Going forward, if you play again with the same group in the future after this, then definitely consider using one of the character generator resources.
tdcharactercreator.com/
or the iOS/Android app. TD Character Creator requires internet access for on-the-fly changes while the app does not.
Have fun! Path of Death is an awesome dungeon
Classes Played: Barbarian (65 times), Monk (56), Ranger (33), Rogue (25), Cleric (21), Fighter (13), Druid (12), Paladin (11), Dwarf Fighter (10), Bard (7), Elf Wizard (2), Wizard (2)