The Cull Father is an excellent DVD, teaching the versatile moves very clearly.
Months later, after watching clips of The Roadrunner Cull, I decided to buy it as well. As excellent as The Cull Father is, The Roadrunner Cull is even better. Much of its value, as Dustin mentions, is in the performances. Even burning his hands, I can't tell that he's culling half the deck! I know what he's doing, but I can't believe that he's doing it so quickly and cleanly. Yikes!
I wish it was a common trend to not only offer 'real' performances of the routines, but also to offer multiple performances of the same routine, as Kimlat does. The Roadrunner Cull offers much on the nature of performing, as well as Kimlat excellent and thorough teaching his specialty.
It's too bad that both DVD's arrived in the same year, since they both offer much for the magic community. That said, if you can only afford one, I think The Roadrunner Cull has more to offer.