Ouch. A bit harshly put, IMO, but sxc is completely accurate. The walls are high, and you won't really be able to share the experience at all. Book CX 256 out of LHR, and you'll get a 343 with the old J class and not have the wall problem. Be aware that all 744s now flying have the new product, complete with the walls in J. 256 continues to be served daily by a 343 without F, so that should solve your problem.

Alternately, if you have some miles to burn, go for F on one of the other three daily LHR-HKG flights, all 744s with the new product. The seats are wide enough that you can sit next to each other in the same seat (except when the seatbelt light is on) and watch movies, or whatever.

Be forewarned, though, after flying CX F you may never want to sit in the back again.