I've been researching different transmission rebuild options and I just cannot figure out the real differences between the different companies.

All the aftermarket companies are quite a bit higher priced and pretty close in price range ect. However if you go and buy a master rebuild kit from Raybestos they are less than half the cost or a 1/4 of the cost of BD if you have priced their kits.

It all leaves me wondering what are the actual differences are between the rebuild kits. Does anyone actually know? Or are the aftermarket kits just using the same friction materials as raybestos and other companies? I'm willing to pay a pretty penny for a truly better than stock product but how do we really know? Each manufacturer claims theirs is the best this or the best that ect. Leave me wondering how much has to do with the internals and how much has to do with trans tuning.

My trans in question is the 68RFE.