As mentioned earlier, some pumps do better than others with the constant off/on. The soft start feature is supposed to help reduce the wear and tear by slowly starting the pumps instead of the sudden surge in power. Still, some pumps handle this better than others. As far as powerheads go, Red Sea recommends MaxiJets as they seem to work the best. Most people that have used the wavemaker agree that the MJs are better than others. For larger pumps like a Mag 9.5, I have never heard how those work under such a setup. In my opinion, the Wavemaster Pro would probably work better than a simple timer shutting them off and on constantly.