Replying to K2 Domain Sizing?

So I'm looking for new skis this year and have my mind set on the Domains. But my only question is what size. I'm around 5'5/5'6, and weigh around 105 (thats a really big guess)? I ski 50% rails and 50% park. I ski at a mountain that gets some fresh snow but not a whole lot, but if there is fresh i will ski it (We're talking 6inches). I ski aggressively and hard. Please help me chose between the 159 or 169. I would like these skis for 2 seasons.

+k for helpful responses.