When you say WC, do you mean the one with dual construction that accepts normal bindings, that you can buy in the stores? If so, I'd say don't buy em. I don't like the way that ski skis.
If you mean the real World Cup ski (full laminate), then its up to you... but I'd go longer. I am 5'10 150 and I ski a 185 in GS. The more torsionally rigid the ski, the longer I think you can ski it.
If you can't get the laminate, buy from a company that will sell you laminates. Its too bad that you don't like the fischer, but I think that the 183 is a better ski than the 178. I find that the Volkl is quite good as well.
[ January 30, 2003, 05:35 PM: Message edited by: sanchez ]