Midwestern (Chicago suburbs) weighing in here:
I voted BK.
I spent about a minute agonizing between Wendy’s and BK.
I finally decided - Wendy’s has too many “cold” ingredients to its burgers. They make a respectable burger, but then they add cold lettuce, cold tomato, cold onion. This throws off the whole temperature of the burger. I’ve never had a Wendy’s burger that arrived at a proper temperature - the cold ingredients overwhelm and I end up being served a luke-warm burger.
McDonald’s beef tastes to me like it’s either full of filler or cooked to death. Not bad, but tasteless.
Sonic - shit.
Jack in the Box - this is the one I can’t comment on, I’ve never been to one.
Dairy Queen? Please. In my 'hood, they’re only open about nine months / year. You go there to get ice cream, not a burger. I strongly doubt they move enough burgers to keep any sort of “fresh” hamburger.
Carl’s Jr (Hardee’s) - they make some nasty (but delicious) artery killing “indulgence” burgers. I probably would have voted them but they’ve all but disappeared in my area.
White Castle - shit. My brother really likes WC; I can’t fathom why. It’s cheap and open all night; that’s pretty much the selling point. I’ll eat there when I’m drunk or desperate, and it’s not terrible, but let’s have no delusions about it being good.
In&Out - this franchise is a great fraud, IMO. I don’t have any local establishments. It was with great anticipation that I finally ate at one a couple of years ago on the west coast. I waited in line nearly 20 minutes. Finally got my burger, prepared for an indulgent treat, then…WTH? It’s a lame-ass, plain-vanilla, dry burger. Hugely overrated.
BK - who got my vote - far from perfect. Tends to be too messy (overly huge cuts of lettuce, mayo applied Pollack-fashion)
But at least it tastes like meat. The “flame-grilled” Whopper, while probably the same meat+filler as McDonald’s - it’s got a bit of a “burger” taste that McD’s has never done.
So BK gets the nod, for a fast-food burger.