The colors blend so well to my eye. I'd use only one row of sashing. Having two rows distracts from the beauty of the birds and their colors. When I look at the overall quilt piece my eye stops at the double sashing and then I have to re adjust and continue looking at the rest of the beautiful focus fabrics.
But, if that's the look you want, go with the double sashing. Beauty is in the eye of the beholder!