Replying to Rossignol FKS 140 vs 180 and where to set my din

I have a pair of amplid townships that I'm going to put one of these on. I ski all park on these skis. I am an aggressive park skier and hit all sizes of features hard. I want to set my din at an 8, but some people say that setting the din that low on the 180s it could fuck up the forward pressure, but I want them to last me the life of the binding, I don't want to grow out of them. I'm 5'825 and 125lbs. What should I do?