I also ate at Jinju, forgot about that. May have eaten at some of the others you listed throughout the years, Despos; though K-BBQ isn't always eaten when sober.
Basically, I think what it comes down to with these Korean restaurants is: 1. charcoal fired grills? if yes, better, if not, at least grate over gas. Cooking on an iron plate (or worse yet, not cooking it yourself) is least desirable, needless to say. 2. what cuts of meat are you choosing? For beef, choose something unmarinated, like boneless short rib (galbi sal), something like that, don't cook it death like Koreans do, and see if you like it. Forget the marinated meat and enjoy the flavor of the meat itself with basic seasoning, and as a ssam. Pork belly (samgyubsal) is also an obvious choice. Beef diaphragm and tongue are pretty good. 3. banchan is important because it indicates the quality of the restaurant (quantity and quality are both important here) - but all restaurants give banchan of some sort if you order the spread, so the differences are subtle. Only really ever been to one Korean restaurant across the Midwest where the food was not the same, and that was because the Korean wife died and her black husband took over the restaurant, and the food became a caricature of what it was before. Mexican staff in the back of the house is pretty common in all of these restaurants. I had pretty good Korean food in Bloomington IN well over 10 years ago and noticed the staff was all Mexican back then.