24 Diner opened up to much fanfare in the old Waterloo restaurant space next to the existing Waterloo Records. A 24-hour diner? With locally-sourced foods? A collective “whaaaaat?” eminated from Austin. A collective “woooow” eminated shortly thereafter, upon the restaurant’s actual opening when it proved that its chicken-and-waffles, hearty breakfasts, great beer selection, and killer…