WHYB to be honest, EOT will do really well, will probably be a top 10 hit and go platinum in the US with around 3m copies worldwide but WHYB will be massive
But if Beyonce does crazy promo for EOT, maybe the effect on her album sales will be greater. I say this because WHYB is in the vein of WFL, and despite smashing WFL didn't do wonders for her album sales.
At this point Where Have You Been has a bigger chance at smashing harder than End of Time. But if Beyoncé really pushes the song and promotes it like crazy, you'll never know.