Our 15-year-old terrier has been having a really hard time with the summer heat and humidity -- we don't have air conditioning .
I was misting her with a hose, rubbing her down with a freezer pack , etc. Then I saw the Ruffwear cooling line. I thought the vest might be too much for her so I bought the gaiter. She seems to really love it and it's made a difference. A lot less heavy panting, which at her age probably means less stress on her heart.
I recommend it. I sized it a little loose because she has a lot of hair and she's pretty sturdy in the neck and shoulders. I'm guessing the gaiter would work even better on a short-haired dog.