RON92 works fine with X-Trail, my only beef with it is that I get slightly lower mileage. My numbers shows that over time there was no significant dollars and cents saved using RON92 compared to using RON97. Then again my data could be wrong.
Don't know why so many folks were afraid to use RON92. It says very well in our user manual the X will only require a minimum of RON91. Chip's RON List in Motortrader also recently got updated with RON data from Nissan. I was shocked ETCM said the X was not compatible to RON92.
Earlier on, one of the reasons I heard for this was that ETCM did had always played the safe side of things. Less issues with warranty.
Take away notes from this post for those still having doubts on RON95 :-
X-Trail works with RON95 !!!!!
Now go worry about something else :)