Not for me
I thought the fitting process was pretty neet, fitment of the bottom component was nice and snug, fit pretty good. But it didn't help my snoring based on the wife's usual elbow to my side. Tried it for a week, no improvement. So I tried the top component, fitment on the teeth was fine, but it left a gap on the roof of my mouth making it fill with saliva and hard to swallow. It was uncomfortable to feel like I was drowning all night, which kept me up more, therefore I wasn't snoring as much... so I don't consider not having a restful night as success.
I can see it working for some people, I must be in the % it isn't helpful for.