i dont know anything about the serpent, but out of the wonderboy and the kpro i would say the kpro. i have heard about wonderboys breaking very easily, and i didnt like the one i used. kpros are durable and fairly light.
i gotta say go with the serpent, there really light, nice and strong and look better than the other 2(proud owner of a black sc1 and soon to be orange one)