I had the cumin lamb burger. I was not impressed, the burger was not very spicy, the meat was dense, the bun was hard and overall it was difficult to eat. There was a huge puddle of oil at the bottom (see pictures).
I had a bite of the original chicken burger and it was much better than the lamb burger, because the chicken was more tender and voluminous making it much more satisfying to eat.
There isn't much room to wait but fortunately it wasn't busy when we went. Overall, you might need two burgers, or a burger and something else to be satisfied.