For S18 last year, trial lessons were essential in picking a school and teacher. His own personal experience was the lessons always seemed to help in admissions, and did not hurt even when S18 did not have his best stuff at the lesson. He had lessons where the teacher talked openly of wanting him at their school, before the audition had even occurred. At the most competitive music admit to which he applied, he did not think he performed well at the practice lesson and the teacher was hurried/distracted, but after the audition he was admitted with a large music talent scholarship. So did not seem to hurt. It’s expensive and time consuming, but do as many as you can.