I haven't actually had lessons with Sarah but had a few with someone on her yard who she trains and watched her teach.
Depends what you are looking for, is it to ride one of her horses and have lessons or on your own?
Sarah is very direct but seems nice. All the horses that I saw her teach with (which were her own) wear Draw reins, infact everytime I saw anyone ride, the horse wore Draw reins. I don't really like use of training aids, but she does seem to get good results.