hopefully I can help. You are the same height and weight as me and I had a pair of the 184 rocker 2's last year. I had mine mounted 6cm foward of what they recomended last year allthough those markings have moved slightly this season. They felt great if your after a quick slashy ski thats good in the trees. I skied the 192 and they feel much stiffer (there not just feel it as there is more chambered ski porportionly compared to the 184) and if I was more of a steeps skier I would go with those as they are allot more stable, but I like a soft playfull ski so the 184 is good for me.
Just to mention the 170 and 180 are differnt waist widths, there 115 rather then 122. I was thinking of getting a 180 this year as a more allmountain ski but I think ill get the 2012 in the new longer length instead. That is untill the narrower rockers (prob about 108) come out anyway.