If you decide to buy the halo 2s, I'd go atleast for the 170. Might be relevant:
I rode original halos in 182 for couple weeks this season, and felt that they were the right size for me. I'm about 170cm/5'6". They have a some rocker in them so they feel shorter, and they turn really easy. I could do rails pretty good with them, got down lip 2s, superfeds etc. the length wasn't a problem.
"Take your life seriously, take skiing seriously. Try hard and know that you're not gonna make it and use that to your advantage." -Steve Stepp