Now here's a thread!
In Cincinnati, the two famous joints seem to be Terry's Turf Club and Zip's. Terry's had the greasiest burger I've ever eaten, which of course means it was wonderful. On the other hand, the Zip's burger I had was dry, bland, and overpriced. Maybe I caught them on a bad night.
I've had one of those "50/50" burgers at the Fleetwood diner in East Lansing once. The bacon component didn't do anything for me--it left it dry and far too salty.
I can't believe I'm reading people complaining about Five Guys being "too messy". Cheeseburgers are meant to be greasy, that's the point. Of the options listed, I'll choose Five Guys, although I've only had In-N-Out once. None of the others are particularly close to those two (and I've tried all of them).
For me, the best is a place called
Miller's Bar in Detroit. Located not far from the Ford headquarters in Dearborn, Miller's is a windowless bar. They refuse to put condiments on the burger for you, and use the honor system when you pay. It's just the best damn ground beef you'll ever eat.
Best fries? Penn Station, end of discussion...