I have used Cool Power medium green for several years and have had no issues of any kind with it . I do add a touch of Marvel Mystery Oil in with my oil changes . I have a test motor that I ran that has probably 125 nights of races on it , and it still fires up and runs pretty strong . I took it apart to check it out a couple of times and other than a light hone and replacing the side cover gasket , nothing was done to it . It is out dated now , and needs to be brought up to today's standards . Just saying , I have had no issues with Cool Power , and I know that wasn't the question asked , just adding my 2 cents , lol