So having perused the various burger comments from this board and others, I have made an effort recently to try out some of the recommended and not so recommended burgers in the triangle. Please add or disagree, point me towards new "must try" places.
From worst to best:
Charlie's (Charley's? the place on 9th st.) -- I tried this per someone's suggestion here. I honestly think my wife and I must have gotten a bad batch of burger or something. The burger was strangely... tough. Rubbery. Weirdly so. Still I like the place so will be back. Overcooked and with a very bland cheese.
Cookout -- Burgers tend to fall apart. There's nothing really wrong with this burger but nothing really right either. Better beefy taste than Charlie's and it lacks the weird rubbery quality. I have had burgers from here that were badly overcooked/charred to the point of inedibility. cheese is a sauce to these people, and stay away from the apparently boiled bacon. Come for the milkshakes.
Five Guys -- My former standout has gotten overly greasy. These used to be very thin burgers - presumably to prevent drying out (when cooked a la diner style) - served two or three patties to a bun. They've kept the two or three patties but they're larger patties now and tend towards being too dry. Good cheese though, and bacon which is actually crispy, should one be so inclined. Good grilled cheese.
Loop -- Really hit or miss. I've had some excellent burgers from the Loop, and some where the meat tasted... wrong. Like it had sat around too long, or they accidentally added some organs to the grind mixture. A bad one is inedible, a good one is close to very good, with a good beef flavor and decent quality cheese. The damn roll is much too bready for the burger.
Q-Shack -- One of the two places I'll order a burger rare. Almost always a better burger than any of the previously mentioned. I know that at one time they ground all their meat on site, but am not so sure anymore. Very good flavor, tending to not be dry despite their putting a weight on the burger as it cooks (which I very much frown upon). Bacon is crumbled into bits and placed under the cheese, which is usually not what I'm looking for, though it does tend to be crispy. One big positive for Q-Shack is they'll put avocado chunks on a burger.
Federal -- My new tops, and the reason I felt like writing this all out. They'll do a wonderful rare/medium rare burger with a great buttery beef taste. Lots of pepper, really good cheese (I had gruyere on mine) very crisp bacon. Good roll.