I've had a couple of burgers from Byron in Islington. The first one wasn't as good as GBK. The second one was about on a par with GBK.That looks good Sunray. Did an order from the website and damn pricey. There is one that just lunching distance from my work. I will try and feedback. You have built this one up a lot so may get sent the bill.
When The Diner first opened on Curtain Road, the burgers were fantastic - among the best I'd had (on a par with ones I'd had in the States). A few months later, the burgers were half the size, overcooked and bland. I'm tempted to give them another go sometime though.

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