Rider's International is made by/for Dover. Many of the Rider's International blankets come with a warranty.....any rips or tears and just send it back and they will replace it. Keep your original receipt as proof of purchase.
Last December I purchased a light weight Rider's International turnout from Dover and it has a 2 year warranty. So far it has held up very well.
Maybe you can give Dover a call and see what they say about your experience with their product.