I don't know the relative "power" of WWB. But, man... I used it to initially test my first build, and the points of impact on the target were so "all-over-the-place," I thought there was something wrong with the gun.
Then I used Federal Champion, and MUCH better. WWB is crap. It will fire and cycle the gun. But, just don't judge your gun or YOURSELF by the shot groups! LOL!