Maxwell Eder wrote an answer about Salomon Rocker 2 Ski on December 5, 2011
I would definitely go with the 184s. The thing about skis with rocker is that they ski much shorter than skis with a normal camber profile. I'm 5'8 and 150 pounds and would definitely get the 184s. Also since you are most likely going to be skiing these in deep powder it's nice to have a longer ski for more flotation. All in all I would say there is a lot of benefit for going with the larger ski and not much cost since the longer ski will still ski short when you need it to. Also 4cm is not that much longer to go.