The Smarty is the one to get if you're worried about warranty. It will not re-set key cycles, which the BDDL does.
That said, I think the BDDL (I have a Triple Dog) runs great! Not a ton of power, but enough to make the truck more fun to drive.
On edit:
The BDDL will also set a P0633 (key code not in ecm) code if you have a grey key. It cannot be cleared w/o a DRBIII.