I have one boy with the modified schnauzer cut. I have one girl with the standard long hair, one with semi long hair, and one with a shorter cut. Also a puppy (5months) with a puppy cut. I go by their look and personality. My Krissy hates to be brushed so short it is. Chelsey loves it and I brush her every night to keep the long hair nice.
I like having lots of Yorkies so I can have lots of different styles!