I consider this cocktail a great success. I used Bullitt rye, so I don't think the brand is important, nor do I think the brand of sparkling wine is important. I also had my local bar make it for me with Corsair Dark Rye, and didn't notice a major difference.
I had to sub some lemon juice because I was out of sumac, and I skipped the hot pepper because I have sensitive people in the house, but this ezme was still fantastic. I made it a second time using sorrel instead of parsley, and this gave the tartness of sumac without adding lemon.