So I had a flight the other week on AA and that allowed me try out the new Emerald Lounge at T8. It's quite nice. But one big bit of advice, most of the good stuff, including beverages, have to be ordered through the menus via QR code. If you've been to the FlagShip lounge in T8 in the past, you will find the buffet and drink selection a downgrade, especially looking at what's out in the open.
Also, I just hope you like British food, because it was a lot shepherd's pies and mushy peas in small quantities on the menu. Buffet selection was a bit more diverse.