i had a Storm traction diff in the centre of my Kanai & it made it almost undrivable!
the storm traction diffs aren't a proper Torsen as you can tell from the arrangement of the internal gears!
they are more like a planetary geared diff & due to the angles the teeth are cut at they seem to give a front/rear torque split with the bias to the front wheels, i estimate about 60%! this for me made the car too much like front wheel drive & made the car push on everywhere[:'(]
try using a standard centre with 7 or even 10,000 silicone & you should notice a marked improvement
the TCD diffs are called LSD diffs in the manual so they are one & the same, its just different translation!
there are no Limited Slip Diffs as such available for 1/8 buggys that i know of!
heres a link to an explanation on Diffs http://www.twf8.ws/new/tech/tip/diff.html
Nuova Faor make "Real" Torsens for the MP7.5 & according to UK team drivers these are the only Torsens that work in the Kyosho