I am currently shopping for skis, I have been renting them for the past five years and this year I am deciding to make the big purchase. I am 5ft tall, 140lb women and I am unsure what length I should purchase. I am an intermediate skier who sticks to mostly blue diamond and black diamond runs. 

I was under the impression that a 150cm ski would be a good fit. What the advantages/disadvantages to shorter/longer skis? What length do you feel would be best suited to my stature?