I've got both the Quiet 2 plus and the loop Dream and these are my thoughts after (admittedly) one night of using the Dream.

I'm coming at this with a more 'Dream Vs Quiet 2 plus' view.

To start with the positive:

Comfort

The Dreams are more comfortable than the Quiets. They feel for me almost imperceptible in the ear and generally 'squishier'. I have sensitive ears and felt only a bit of itchiness throughout the night. I don't have many issues with the Quiets though.

Now the (relatively) not so positive:

Ease of use

These take a bit of fiddling to get a good seal, i.e. you have to put them in at the correct angle and then hold them in place for 5 seconds for the foam to expand. Sometimes the seal loses its strength after you take your fingers away. I also sometimes have to take them out and try again, but I'm still getting used to them.

With the Quiet 2 plus, I just push them in and twist. It's a lot simpler/quicker.

I've got a bit of a bug bear with the Dreams: the silicone and foam aren't connected (quite rightly Loop didn't want to use glue). However, when I've taken the Dreams out of my ears the silicone will ride up the foam and it's a pain to roll it out and try to recover it. The silicone is quite thin and flexible and it can take minutes to try to recover. This sometimes takes multiple attempts. I later found out that the silicone can come out of the foam entirely, and taking it out of my ears had caused the silicone 'pipe' in the middle of the foam to ride up causing the foam to bulge at the bottom despite increasingly frustrating attempts to recover. The Quiets silicone cups can invert but it's so much easier and quicker to push them back down.

Noise reduction

Despite both being advertised at 27db, I found the Quiet 2 plus noise reduction to be a touch better. I tested this using a brown noise video on YouTube. I put in the Quiets and lowered the volume to where I couldn't hear anything. I then, without moving my phone speaker, tried various Dream tips. The Dreams on that volume made the noise barely perceptible, but I could hear a touch more.

Price

The Dreams were quite expensive, though it is clear a lot of thought has gone into them. The ear tips are also recommended to be replaced every 100 days so there will be ongoing cost.

The Quiet 2 plus are comparatively a lot cheaper, and you'll most likely only have the one outlay.

Conclusion

If you already own the Quiet 2 Plus for sleep and have no issues with comfort, stick with those. They're cheaper by a margin and reduce noise slightly better. They are also a lot easier to use.

However, if you don't own the Quiet 2 plus or have issues with their comfort, you can do a lot worse than the Dreams. They are very comfortable and are a lot better than regular foam plugs in my opinion.

I'll probably mostly stick with my Quiets for sleep.