The real problem with a suggestion box: time
A suggestion box is a feedback channel, not a response channel. A form written when the restroom ran out of paper towels or the waiting room air conditioning broke is out of date by the time the box is opened. The problem has either gone away or hit more visitors.
In EnaFeedback, feedback lands in the panel the moment it is sent. Complaints get high priority automatically, and you can turn on alert rules for complaints or low hygiene scores to notify the person in charge by email, SMS or in-app notification.