If you value comfort of the seat / bed, CX wins.
If you want good foods and good wine, JL wins.
If you want good services - then it depends on how you define it - CX FAs do not bow to you and would not be submissive. They do not watch you to anticipate your needs but they would rush to your side within seconds you press the call button which on CX F is truly meant to be used to summon the services.
JL FAs would be oh so submissive (but generally more to the male passengers and especially to the Japanese male passengers, and often neglect the female passengers) and being around the cabin far far more often.
So if you prefer to be left alone and when you want service you summon it - then CX works a lot better.
If you want to be constantly looked after, then JL (or SQ for that matter) would better suit you.
Personally I dont like the JL seat set up, nor the cabin temperature. Much prefer the openness of the CX seat set up and the cabin temperature. However the CX foods are mediocre. But since the quality of sleep is the most important to me, plus I dont like the need to transit in TYO, hence always pick CX over JL.