I originally purchased a competitor's mouthpiece and loved it for years. When it wore out, I ordered a new one from them and learned that they changed the way the mouthpiece works. The mouthpiece wouldn't fit in my mouth very tight and my lower jaw would slack and my wife said I snored like crazy again. After some research I found PureSleep. When it arrived, I followed the directions and fitted the mouthpiece to my mouth. Immediately I noticed that this mouthpiece fit better than the previous companies did. The fact that there are no screws to adjust this mouthpiece is a huge plus for me. The competitor's mouthpiece advertises Infinitely adjustable with the screw. This screw, however, strips loose during the night and no longer offers the anti snoring benefit. Puresleep doesn't have adjustment screws so the mouthpiece stays in the position you originally formed. It is also much more comfortable than the competitors because it doesn't have those same screws tearing up the inside of my cheeks. This is saving my wife's sanity and I am also getting better sleep.