Some are big and bulky, but many aren't. I'm running in the 825 right now and its extremely flexible and weighs less than 10 oz. I never wore NB before but I've been very pleasantly surprised by their products in the last six months to a year.
Anyways, saying you don't like a brand and saying they're making the worst shoes out there are completely different things. I can't wear Brooks at all, they tear my feet to shreds, but I still think they're one of the better brands out there and they sell well at the store. They just aren't for me.