I remember jap explained the 6 speed tranny to me so that way anyone could understand... you have the same tranny housing...instead of having 5 gears, you have 6...so what did the mitsu engineers do? the made smaller gears to fit in the same tranny housing that the 5 speed has..and when something is smaller it tends to be weaker...

and yes the se is only for 2006 which all 2006's are evo ix's..and instead of having mr badges everywhere in the interior it says se everywhere. (special edition if you were wondering what it meant)

p.s. if you dont plan on going over 425hp, the 6 speed should be fine