I flew in the 2-3-2 J cabin in 777 recently on a aisle seat next to the window. The middle seat isn't that bad as it looks on the seat map - I would say that it's better than window seat, as nobody steps over you and if you need to step over the pax next to you, then you can pick one of two and pool it if you drink too much (I'm big enough to step over them w/o them disturbing when sleeping.)

Though I'd suggest if there is A380 on your route, pick that one. Seats are wider (both only angle flat though, but comfy enough to sleep) and the configuration is 2-2-2, so that the middle 2 block is w/o disturbance.