What would you do??

Ok so i have in my possesion right now 07 foils. They are 166cm and i am about 5'7". They come up to about my foreheadish/ eyebrow level. Thats how ive always had my skis growing up, never above my head but im wondering about a longer ski? im not really sure if its better to have for rails and jumps. Anyways im wondering if i should get 176 dumonts for my height even though there above my head. And any imput on where to mount would be good too, im mounted on my foils about 2 or 1.5 cm back from true center but i hear the dumonts are a more foward ski?? is this true?? thanks guys