Work fine, comfortable enough for sleep
I'm using these for sleep.  They are reasonable comfortable;  it only took a few minutes to get used to them, and I'm acclimated.  Little things discomfort my sleep, so this is a good outcome.  They are quite effective;  you can use them as described, or you can insert them more loosely if you want to only partially filter ambient noise.  They do tend to diminish the effectiveness of alarm clocks, so you either need a loud alarm, or wear them loosely as I've described.
Rating: 5 stars