indeed mine is a 3.55 as well. got it open in the first place to inspect everything and deal with the whole pinion nut rear diff problem discussed on the forum. there was no damage to ring and pinion gear so those were reused.
as for the difference between a standard LSD and this one (correct me if I am wrong). both the standard LSD and this one are limited slip. they are just differently constructed with one beeing a clutch LSD and the torsen style works with gears. this means far less moving parts, so no clutch plates and springs so less to break and go wrong, meaning less maintenance. i supposively only have to change oil every 100000km, thats it. this without LSD additive.
I can't compare the two, I never tried a standard lsd since i went from open to the truetrac. I did notice it locks really fast and stays locked as long as needed. I noticed when the diff should
react it does it almost instantly. it doesnt take a half turn of the other wheel till it reacts. in case one wheel is completely of the ground it could be nessecary to apply the e-brake a bit to bite. again I have nothing to compare too other then an open diff.
VeghTheHun, I think they cost about $600 without installation. i cannot recommend a shop because i had them installed in Europe. If you go with this one you won't regret it. they cost a bit more but are bulletproof and it repays itself by beeing maintenance free.
heres a video, its not the best one but a ram: the black ram has detroit lockers and the red i think other lsd. is it a honest comparisation? don't know, can't see the tires on my small cellphone screen. but you can see the locker work.