What size ski??!!!

Hi everyone.
Really getting myself worked up over this personal debate :x . I am looking to purchase some rossignol soul 7 skis (2015) just do not know the suitable length (180 or 188). I am 17 years old and am a very confident, aggressive skier. I love the days in the powder and exploring but also have the odd day calving and bombing about the groomers. I am just about 180 cm tall and weigh 74kg (163 pounds), I am edging towards the 188s but do not know whether that is too long for my height or not. Also will the 188s chatter alot?
Appreciate the help!
Thanks :)

Have you thought about renting both lengths and comparing before you spend the money?

I think you will be better off with 188. You will lose lot of length due to rocker and 180 might feel a bit short. With this type of skis it's a fairly safe bet to go longer, but if you are not sure - try to demo.

I would strongly agree with both comments above, specially demoing equipment before a significant investment. You even answered your own question to some degree, it's all about the right tool for the job. Do you have a "home hill"?, what conditions do you see most often? The ski you are looking at does not make sense if you can only expect 1 powder day a year. If on the other hand you are charging back-country like terrain every weekend?? Try to demo some different types if you can...