That's a good question. We are using prelubers from Keith Eickert and they work great. Flip the switch and let them run a few seconds before starting the engines and there will never be a dry start. It certainly can't hurt the engines to use them.
We also use them to change the oil because they have a quick disconnect coupling on one of the lines. We simply connect a long hose to the quick disconnect and run that outside of the boat to collect the oil. Once that line is connected, all we have to do is flip a switch and wait a few minutes for the oil to be pumped out of the engine. It doesn't get any easier than this.