This winter I hastily threw together a 12 volt Shurflo 4008 setup on 75 of my taps. I am highly impressed with this thing. I used to have "real" vacuum and an electric releaser on 1000 taps, and did not expect much from this thing. I have to say that I am amazed with how well it is working. My laterals are new and tight, with no squirrel chews (yet), so no air leaks to deal with (yet). I am getting more sap from these 75 taps than my other 140 or so on gravity. I do not even have a recirculation line, either.