Interesting. There are a bit expensive but I like the idea of turning a valve to drain. I have a magnetic plug on my fleet currently and kind of enjoy pulling them to see if there is any particulate captured on it. I guess with the quik-valve, that would not be an option. Do you have the F-104N?If you don't want to fool with "hot oil" I suggest folks look into the Fumoto Quik-Valve for their specific Volvo engine. I love mine on my S80. I have them on several of my other cars as well.