Product review (2 stars): Decent concept - poor execution
I liked the idea of getting a better seal on my dryer vent, so I decided to try this. I wish I had not.  First, it doesn't come with the vent tube attached like other vents, so you have to go find one (especially if your old one is a bit corroded).  Second, having found one at the hardware store, I inserted it, but it wasn't a very firm fit.  So I pushed it in a bit more firmly, and the elbow split apart at the seam.  Consequently, I then had to get several large matching wire ties to wrap around the elbow tube to make it stay together.  Even then, there were gaps that needed to be caulked.  The vent pipe also needed to be glued in place to stay firmly in the hole

On top of all that, unlike other vents, because of its size and weight, this unit really won't work well without screwing it to the wall as shown. Two problems with that.  First, they dont' provide the screws, and, even if they did, ordinary screws wouldn't work for stucco.  Second, the manufacturing is sufficiently poor that the mounting base on the bottom piece does not come close to lining up with the mounting base on the top piece.  So the top piece is out about 1/2 to 3/4 inch from the wall, and not screwed on as shown on the picture.  Forcing it to the wall would likely have broken it.

So, I have now (i) gone to the hardware store to purchase the vent pipe, (ii) gone to the hardware store again to get the giant wire ties to repair it, (iii) gone back again to get the caulk and glue needed to seal the seam and keep the pipe in place, (iv) finally found some screws that will work on stucco and have a whitish color on the heads that will match the vent, (v) put new holes in my stucco wall to mount it, and caulked all around to seal the edge as well as the seam.  And even with all that, it still looks like it's not completely mounted correctly because the top portion just wouldn't line up.

With all that, does it work better than an ordinary vent?  Yes, I think so.  I like the comfort of having the perfect seal now when the dryer is not blowing, and now that the weather is getting colder, my wife is pretty convinced that the laundry room is not as cold as it was in prior winters.  On the other hand, the lint tends to accumulate all over it, especially on the warmed caulk.  Also, if you're just worried about small animals, there are vents with built in guards on Amazon that would look to be just as effective.  But this vent would certainly do a better job than anything else of keeping bugs out, if you have an issue there.

But it just wasn't worth all the hassle.  Would it be worth it if they included an attached vent pipe, had better manufacturing quality and included an appropriate assortment of screws and maybe sealants?  Yes, I think so.  And it would have been worth an extra few bucks for the added cost.  If you live in a really cold climate, it might be worth it even with the hassle, although I wonder if much of the improvement might simply be the result of taking the time to caulk the edges for improved seal rather than from the vent itself.