Thundershirt - Does it really calm a dog's anxiety?

So, I just discovered the Thundershirt. It's a wrap for your dog that kind of hugs them and somehow ... magically, admittedly in some fuzzy science kind of way ... makes them all calm.

Excessive barking, separation anxiety, noise anxiety, thunderstorms, stranger danger - no matter what it is that sets your dog off, the Thundershirt is supposed to be the answer.

Now, there isn't a solid scientific reason given for why exactly this works, but I have found that wrapping my arms around Paisley when she's panicking does seem to help a little bit. But I'm not sitting on the floor with her every time someone she doesn't know comes to the house. I'm ready to try something that might help.

It's been shipped (hooray!) and I will be updating with a more complete review once I have my own experience to share.

Update: I'm kind of mixed on this. Paisley is definitely calmer in general, rather mellow in fact, while wearing the Thundershirt. But it doesn't seem to be helping much in her high stress situations. Could be I'm not putting it on early enough, could be that it just doesn't work for her. I know it works for other dogs, but everyone's mileage varies.