I would just buy the stock replacment. unless you have a bunch of mods that require a higher voltage to fire the cylinders, then the extra money you are spending for a coil that has the capability of releasing more energy is going to waste.
Coils only put out the amount of energy required to fire a cylinder and complete the burn. No more, no less, and unless you are reving past 5500rpm, which is where our stock engines run out of breath anyway, then getting a coil that is capable of faster saturation is pointless anyway.
Jus my