I walked pass this yesterday on my way to Pre-Check. There were many people standing around "waiting" for their turn. Yet, it was only a 5 minute wait at the regular screening. I guess that it was due to the newness factor and learning curve for the employees checking the appointment times. But it seemed silly for people to stand around waiting for an appointment when they could have gone through the regular line. I think there might be value to this when the lines are more lengthy. Especially, since you can sign up for an appointment while at the airport.