I would give more stars... To start, I had noticed a significant increase in my quality of sleep after using this for two days. I'm going to make this review as honest as possible, so others will know what they will get.
On the first night, I had difficulties falling and staying asleep as my lower jaw was not used to the overnight tension of being pushed forward for 8 hours. I recalled waking up with a bad headache, something that never happened to me before. I didn't much sleep that night, but I decided to stick with it and hopefully get used to it in a week.
After the second night, I woke up feeling refreshed. I had gotten accustomed to the tension and had no headaches. I recalled waking up and not feeling as if I need to sleep in any longer. For once in my life I woke up well rested. I had forgotten what mental clarity feels like until I woke up with the silent night guard.
P.S. For those who are curious, I am currently a college student in my senior year. I had been suffering from Sleep Apnea since high school. I developed sleep apnea as I grew older. My tongue was to blame as it was growing larger. This product created more room in my mouth for my tongue to rest on and prevented it from blocking my airway when I sleep. I hope this trend continues, but other than that I am happy with this service! :)