Looking at flight YYZ-CDG return: Feb 1-12, 2014
-if book into Y then YQ is $456pp
-if book into J then YQ is $826pp!
Most of the rest of the taxes/fees are the same regardless of which class booked into (exception is French Air Passenger Solidarity Tax IZ Y is $5.60 and J is $55.60) - so total for Y is $$582pp and J is $996pp plus of course the points needed! Numbers come from ita Matrix search