It's the only tranny additive that has ever received certification/approval from an OEM, and it has several OEMs that use it at that! Use the search function (or Google it), the resident formulator MolaKule actually had some really informative posts, and he also had good things to say about it.
I add it to every used vehicle I buy when I change the ATF, not because it's magic, but because of the cleaning abilities and proven results. I haven't had a single failure of any auto trans I've used it in, regardless of mileage. Still trying to convince my stepson to use it, since he's invested roughly $15k in the past 7 years for an E4OD and two Dodge trannies that did not have power adders in front of them, and all 3 trucks were under 150k miles...