I'm going to say Bey. Britney wouldn't be far off at all tbh. And that's without half the promo Bey does.
They would never dare try each other with the dates though.
But then again, Britney released a hit & Beyoncé released a dud & still sold more so I'm not sure. I always thought Britney had great first week sales so I want to say her but then I don't know cause FF didn't sell as much as 4 first week.
So upset