Just keep in mind "Western Dressage" and "Cowboy Dressage" are two different things!
I only have experience with the former and my ladies are very excited that they can continue to ride in their Western saddles while pursuing dressage, and even go to some of the same competitions as their daughters. Not all dressage shows in the area are offering WD, but I did at all my shows last year with marginal turnout. I am hoping to get a better turnout this year!
They say money doesn't buy happiness -- well happiness doesn't buy horses!