they can last ~9 months, so i've been told.
they look fine, packaged in bulk together and sealed in freezer-safe plastic bags. some might be stuck but a little wiggle should be enough.
frozen rats are delivered priority mail within 2 days of the order, and are shipped with dry ice to keep them frozen. i have never had an issue with them arriving thawed; always buy from a reputable supplier: Perfect Prey, Big Cheese, etc.
they do not stink when they're frozen and have no smell in the freezer; i used to keep them with our frozen food until a spare freezer opened up. there is a smell once thawed but to me it's not terrible or room-filling.
as for a power outage i'm not sure i can help there: you need to keep that stuff frozen; a cooler with ice could help for a while.