Jamie Preston wrote an answer about Volkl V-Werks Katana Ski on April 17, 2014
At your height and weight, one would think 184 at a minimum, but for the fact that you are not overpowering a 176 RTM. Hmmm. The 177 would put to test my theory that most Volkls are going to provide good stability at almost any weight or height. I do have a 178 Gotama that is super fun at that length, which shockingly has never felt unstable, but I never ski it in much snow (because I go fatter). But, the Katana is a powder ski and you want surface area - and given their low weight and low singweight, it just does not seem like you should be worried about skiing a 184 - 177 might seems like too little ski for you given all the factors. As a 6'1" 180 , expert in very good shape with an embarrassing amount of ski days I have been on the 184 and it has never felt like too much ski. But, to answer the question as to whether you could "get away" with a 177 - probably yes. But, you'd likely be happier on a 184.