I've been training with KBs for almost two years, and I would have to say that nothing compares to a KB. I recently started another one of Pavel's programs: Power To The People. The simple lifting and pressing workout he outlines in PTTP is a great supplement to KB, bodyweight, and endurance activities.
You can find all the info here:
http://www.holtreman.net/gg/power-to-the-people/
I hope the information is useful to some PTers out there.
-swim