I have a Jabsco Head on my boat, and, though I know how you feel about Jabsco's, it really has not given me any major problems. One thing I noticed though, in comparison to Jabsco Heads on other boats, is that my tends to pump somewhat "hard". Always has. Feels like there is a lot of pressure build up. My questions are as follows: Does hose length to the holding tank have anything to do with it? What about release valves...should they be opened from time to time? Thanks in advance...