I run a full length add-a-leaf in the rear and have ZERO axle wrap issues. This leaf is simply combined with stock Ford 3" wide springs. I do not 'flex' as much as many people do, but I find it to be sufficient This lack of 'flex' has not been a huge issue anywhere that I have wheeled.

It has seemed to me that one of the most common breaks on the trails and headaches in the garage have been anti-wrap bar related, thus I choose to not have one.