this is kind of a late answer, but I see you posted it in the generation 6 era, so here goes. it would always land critical because in gen 6 a +4 critical hit stage will always land critical.
+1 from super luck, +1 from scope lens, +2 from focus energy, +1 from night slash. thats actually a +5 critical hit ratio, and thats still a 100%critical hit ratio in generation 6 only.
in gen 5 and below, it is less than 100%, but still as high as youre going to be.