For me, of the three long haul J class trips I’ve taken to Europe in the last 18 months, I found the length best on QR but I flew them last year with their poor old style seats before they put Q-Suites on the AKL-DOH route, and the comfort was so-so. I hear good things about the Q-Suites and would like to try them. SQ had really wide seats on both 777 and A380s and slightly better legroom than NZ so that was my favourite of the three as I slept ok with them.