Was wanting to try vacuum chucking, so after thinking about it for a while (and reading that Larry Marley uses the same pump) I bought the 110 volt HF 2.5 cfm pump (in the store with a $74 online price match). I have a very simple setup - if anyone sees problems with it, please let me know, but all I am using is the pump, homemade chucks, a vacuum gauge (Northern) and a pressure relief valve (really not needed with this setup, as the pump bleeds air - and some oil, I think Mr Marley said, so the pump has to run continually - does the Gast version?). Have no worries - my gauge shows a whopping 28 on the vacuum scale with a very good seal at the headstock - if it is true, I for one am impressed.