Couldn't disagree more dude.
Ashamed to say this, but I've been four times since it opened last Monday (In my defense I live about 2 minutes away from the Trafford Centre though.)
Admittedly it is expensive for a burger, but £20ish quid for a casual meal for two is pretty standard. It's easily the best food experience in that food court now. All the burgers are made fresh to order with exactly the toppings you ask for at no extra charge (free extra cheese and extra bacon - the best bacon I've had on a burger) is a complete winner.
I'll hold my hands up and say I love Almost Famous too, but if you've ever had a basic bacon cheeseburger at AF it's not much to write home about, where they excel is all their creative toppings. Also, when I compare going to Almost Famous where I'll expect to wait an hour for a table and subjected to the hipster contempt of the staff to somewhere like Five Guys, which is instant sit down, fast service and flawlessly polite staff then I'll go to Five Guys any day of the week.
I've not been to Byron, but the fact that you can compare GBK's frozen efforts favourably to Five Guys seriously makes me doubt your palate to be honest. (no offense)