So how long does it take for kryptonite to effect Supes? Is it instant? Does it take a few minutes? Cause a few minutes (even seconds), you would have to assume, could provide Supes with plenty of time at one good adrenaline-fueled toss. Even if Supes is weakend and Bats doesn't reach the sun, maybe he gets caught out in an atmosphere with no air? Maybe Supes gets a running start and flies at him at 700 mph? Sure, Supes would come out of that with a broken hand/arm (because of the Kryptonite), but Batman would be jelly in that suit.
Nah, this is like Mayweather/Pacquiao: My heart is on the Pacman, but my money is on Money.