TerraLUX TLE-300M-EX difference with a 4D and a 6D Mag??

[Chicken Drumstick]

What difference would a 6D cell Maglite make over a 4D cell Maglite with this LED upgrade? I've got both but will only be buying on 300M-ex.

http://www.thetorchsite.co.uk/TerraLUX_TLE-300M-EX_MiniStar30-EX.html


I'm guessing it'd be run time, rather than brightness?? 😕