Check out David Francko's book Palms Won't Grow Here and Other Myths. He's based in the Cincinnati area and the book lists some Nandina varieties that do well locally.

I have a plant of 'Moyer's Red' that gets to about 3 feet each year in a south-facing foundation bed and dies back a bit in winter. Makes a nice show during the growing season.

I think someone asked a smiliar question before. Nandina is both a great shrub and dieback shrub, the later of which is how it will perform in zone 6. They do recover quickly, but are still best sited in a protected area. I've had "Firepower" that usually (not always) dies back to the snowline but regrows... Being a dwarf, it is often covered with snow which does help to insulate it and prevents further stem kill... It has great color in fall/winter...

I'm in Oxford,north of Hamilton ( which is north of Cinci). I don't know the cultivar of the one I have because I got it in a trade but it dies back every year and comes back. I'm thinking of moving it though because it never seems to get started early enough to get berries on it..it blooms but just barely before the frost gets it.
Mary