I tried GBK as it was the closest burger shop that wasn't McDonalds still open after a shopping trip at Gerrard Square. I regret it, I will never go back, and I tell all of my friends to avoid it at all costs.
I ordered a burger, fries, and a drink which cost a fortune. And then I waited. And waited. And waited.
While I was waiting the whole shop filled up with smoke - do they not have exhaust fans back there?
The service was mediocre, with the kitchen staff and the cashier literally shouting and swearing at one another.
When the food finally came out I realized I had made a terrible mistake: the fries. There are so many, and they are so bad. I would not recommend ordering fries if you're craving a burger - I'm not sure who could ever eat that much food in one sitting.
The burger itself was pretty lame too. It wasn't terrible, but it wasn't great. It gave me food poisoning, which had me bedridden for over a week.
The only thing I truly enjoyed was the (overpriced) Canada Dry Ginger ale I ordered.
Basically: don't waste your time. Hero burger does it far better.