Surprised this was downvoted because it's dead on. Turnhouse easily has the best burger compared to all the other places listed in this thread. Manor Hill Tavern and Victoria's do come close. Only other place I'd throw in is Frisco. Might be a little step down in quality, but it's a bit cheaper and probably has the best beer selection in Columbia.

And Turnhouse definitely occasionally has incredibly slow service. Depends on the server. Sometimes we're in and out in 45 minutes, sometimes basically the same order takes twice as long.