Best warranty
However I wouldn't be sucked into the warranty as much as the reputation of the builder. A warranty is worthless if you have to use it all the time.
We back our products and most good vendors do, even sometimes when it's out of warranty or an installer error.
We aren't doing 4L60E's yet for shipping, only local customers but I'm sure that one of the other vendors here can fix you up or refer you to a good local builder maybe.
Being in the business youself and building these transmissions for the dealership, you know first hand how these transmissions function. It takes a skilled builder to make one hold up in a performance application. Unfortunately local builders usually don't have the time to R&D these units to figure out the modifications required to make them hold up in a performance application.
We aren't the cheapest in the business, but our reputation with 4L60e transmissions speaks for itself. We build over 300 units a year and have the fastest 4L60e transmissions in the world.

