I would point you to the discussion on the newest seat "New 777 J seat to be announced soon" to read criticism and praise for the J seat/service. Emirates does do a lot of advertising and they do it well to say that their seats are 'luxurious.' I don't consider it the best J seat in the world by a long shot but it is not as terrible as many people would have you believe. If your choice is between those 3 airlines and a flat seat itself is the most important factor EK is angled at about 170 degrees. If the Qantas flight is operated by an A380 or refitted 747, or refitted A330 then you may get a flat bed.