It's not First, it's Business Elite (BE). Very nice flat-bed seats on the refitted 764s, entry by 2L means once you've boarded you can relax without people traipsing through the cabin (the big advantage over the revamped 763s). Tall people don't like these seats as they have a hole for your feet and if you're taller than that cut-out you are out of luck. Seat is quite narrow, no problem for an averagely-size person but problematic for larger people. You'll get champagne-like wine before takeoff, lunch, then snack before landing in ATL. Booze flows well owing to usually attentive and friendly cabin crew. IFE is ok though movie selection is not so hot on the indie front. Noise-reducing headsets are provided free of charge. Blanket and pillow are cushy and nice. Toilets can be a problem. There are only 2, at the rear of the BE cabin, and 1 is frequently not in use (reportedly held back for pilot use, but this hasn't been conclusively established, though I personally report it happens A LOT). Pre-departure lounge in LHR is very nice, with Clarins beauty treatments available, and "sleep" rooms upstairs for privacy and napping. Heavy snacks available, very airy and light venue. You will land either in E or F in ATL. I haven't tried the lounge in F, but the lounge in E has recently been revamped and it's ... ok. There are showers, so if you want to freshen up before you continue to Miami, make sure you do so before going to your next terminal lounge. There is no FastTrac on the ATL side so immigration can be slow. You have to retrieve your luggage in ATL before rechecking it and entering the terminal. On the way back to LHR it's faster as you get a pass through Immigration if you travel in BE that allows you to skip the big line. I think that covers it!