Hi, I have had one for about a month. My mare has always reacted to being girthed up by trying to nip, she no longer does this. I would say that it was worth the money as I think she is now more comfortable.
I have found the perfect rug; just as you described! Premierequine- Winterbuster, on sale as we speak: http://www.premierequine.co.uk/acatalog/Sale.html
I have two and they are great