If its old J on LH, then avoid like the plague. Had the worst flight I've ever been on in old LH J. Seat was more like a dentist's chair. Cannot comment on new LH J, and I hope I never will, as I hope never to set foot on an LH aircraft ever again. LX on the other hand....

BA F has its foibles, but overall it's a pretty good service, Seat is comfy, food is reasonable, and the CC are usually lovely (unlike one on LH I could mention). However, DXB to DEN does make me think of using one of the ME3.....