Only one visit to date and I tried the cheesesteak with just onions and cheese. I must say, it was pretty good. Fresh bread, good ratio of filling to bread, cheesy, drippy, flavorful like a cheesesteak should be. The only negative was that the meat could have been seasoned more as it was grilled up. After the first bite I had to add a good dose of salt and pepper before I finished.
Haven't quite figured out their schedule yet as they seem to appear on random days at the corner of Third and Tryon. Could be I'm just random though and can't keep track of what days I go look! :)