first time trying shack shack and was pretty excited! food was great. shack was a little too thick and fattening but tasted great with my burger :) service was on top! servers kept themselves busy, i was pretty impressed when they got me a refill of my coke zero because you don't expect that at a fast food place. if this was a restaurent, i would've left a 30% tip for them. great food, just a little too crowded because this just opened in AZ for the first time so i'll come back again in couple months.