Power cord length?


If I'm going to spring for an uber expensive cord-a 'final' purchase-say an MIT Oracle AC 2--is there any sonic benefit going to a 4 meter vs a std 2 meter? (I have absolutely no chance to audition). Technical details of 12 ft versus 6 ft power cord?
ptss
I will also add, In all my exsperience with Tara labs cables, with all lengths, other than power cables that I do not have extensive exsperience with, No Tara labs cables has ever had a forward sound, so likly their reply will say the same, I'm currently not using the power cord untill I get my digital player, cannot use it on the amp, the power cord is hard-wired onto the Krell 700cx amp, cheers.
Tara labs said, their is very little, if any presatation difference with 3ft, 5ft, 6ft with the Tara Labs cobalt power cable, and the presatation in no way is forward sounding period, cheers.
The difference between 1 metre and 2 metre powercables from Nordost was very clear. There was no education need for it!! I did compare Vishnu and Valhalla 1 metre with 2 metre.