Karen has a lot of knowledge and experience under her belt. She has shown at high levels and is also a judge (the highest you can go). What she teaches and how she teaches it, to both horse and rider, is exactly what I had been looking for. She incorporates the parelli principles into her dressage training, which is why she calls it Dressage, Naturally. It's quite different from "traditional" (if you will) training styles.
I will choose someone who puts the horse first and has the same principles and values as myself. I will not choose someone just because they have a good reputation in the sport. That doesn't necessarily mean they put the horse first, it might just mean they are good at getting the job done.