I just put mine in the garage brooder this afternoon, and they seem to LOVE the space.
My only problem so far is that whenever they hear/see me they get up from wherever they are sleeping and go running/flappy around the brooder, start eating and drinking like crazy, and just in general think it's party time! I can't tell if they were huddled or not, but since the box is HUGE compared to their old one (with plenty of room to get away from the light) I lowered it a bit just to be safe, and stuck a thermometer under it just to be sure.
Glad to hear your babies weathered a storm! How did they react? I'd think that could be pretty scary for them.