I love marble slab!!! It's cold, it's thick, it's customizable, and everything tastes great. PLUS the default cone is a delectable waffle cone (that looks like it's made in store?) instead of those gross sugar cones you get from the trucks.
You can choose whether you want something fruity, sweet, or salty. They have so many choices of fill-ins, it's really hard to decide. I usually just modify one of their recommended cone combinations.
I think it's pretty funny how they weigh the amount of ice cream before they put it on the cone. Guess this prevents them from giving you too little... which I appreciate to a certain degree.
They also sell birthday cakes, ice cream sandwiches, and pints of ice cream at the side, so if you're down for something to take home for later, that might be a better option.