I had the Castor burger, and it was excellent. The burger was moist, flavourful and the toppings were delicious - there wasn't too much (or not enough) of any topping to overwhelm the flavour of the burger.
I see the fries are receiving mixed reviews - I personally like the chunky cut, and found them to be slightly on the well-done side (which is how I prefer them).
The setup of the restaurant, however, isn't great - there is very little seating and you have to go to the back of the restaurant to pick up your burger. For some reason, they have placed a massive bar that takes up a good part of the restaurant in the centre - maybe they do shakes or something? There are no tables - just a bar against the wall to sit and eat. I wish the layout was better, but the food is worth going back.