I've experienced a lot of chargebacks, unfortunately. For some reason some gang of people from Vietnam keeps using my site to verify stolen credit cards work. Originally this all happened through a third-party service which I had no control over (I couldn't preemptively block suspicious transactions). I switched to Swipe and eventually saw the same fraudulent transactions coming through (one was 50 charges with the same card with a minute of each other).

Sick of it all I finally got minFraud setup and working with Braintree as the payment processor. So now, I use Braintree to authorize the card, then do a fraud check through minFraud. If the fraud level is low enough, I submit the payment for settlement, otherwise I void it.

Since putting minFraud in place I haven't had any chargebacks.

Why not do the minFraud check before auth? Won't that save you some auth fees?

minFraud is a very cost effective service. We have them as one of the solutions in our platform.

There's no fee for an authorization. That's just the check if the card is valid. The fee comes from submitting the charge for settlement.