Replying to Im sorry to ask this again but

im sorta nervous about skis this season. I really cant decide between the ninthward comte and the fischer addict. I felt this question needed to be asked, seeing that i am a sorta average size for a 15-16year old. i am 6ft, 155, and still dont know which length will be better for me, 181 or 176. i would be mounting true center and using the skis for park only. will 181 make it harder to do rails, or will it be manageable? i am no expert. last year i skiied on 167foils mounted a little back, and they were obviously too short but i have grown since then. help me please.